some of the more popular VSEs,from Wikipedia:
All in the Family -
* Gloria is attacked and molested by a man on the street and the Bunkers argue over whether or not she should report it to the police. (1973)
* A Jewish radical (Gregory Sierra) who is trying to stop anti-Semitism in the neighborhood is killed by a car bomb outside the Bunkers' home. (1973)
* Edith is attacked by a rapist (David Dukes) on her 50th birthday. (1977)
[a VERY good episode

]
* Edith sees her very close friend murdered. (1977)
All of Us -
* Bobby (Khamani Griffin) uses the word "n---er" at a get-together which causes the adult who overhead him start debating the seriousness of the word. The show ends with a short video of the word "n---er" and other racial things being used in society over the years. (2006)
Beast Wars -
* Dinobot sacrifices his life in order to save the lives of pre-humans from Megatron. (1998) [My nephew's son was tearing up at the end of this one..]
The Cosby Show -
* Cliff helps a friend cope with his daughter's addiction to cocaine. (1988)
* Pam is pressured by her boyfriend for intimacy. (1991)
Degrassi High
* Dwayne discovers he is HIV positive. (1990)
* Claude commits suicide in the men's bathroom after he is dumped by Caitlin. (1991)
Degrassi: The Next Generation
* Ashley takes Ecstacy at a party, which ruins her reputation. This episode featured a viewer discretion warning about the consequences of drugs, and a special message from cast member Daniel Clark. (2002)
* Paige is raped by a soccer player from a rival school. (2003)
* Marco comes out to his friends. This episode had a viewer discretion warning. (2003)
* Manny becomes pregnant after having sex with Craig and has an abortion. (This episode did not air in the USA until 8/18/2006.) (2004)
* After Rick is tarred and feathered, he returns to school with a gun, causing a school shooting in which he is killed. This episode had a viewer discretion warning about the dangers of violence in schools. (2004)
Diff'rent Strokes -
* Phil attempts to enroll Arnold and Willis at his old prep school. Willis thinks they won't be admitted because of their race, but the recruiter (Howard Morton) informs Phil that the boys won't fit in because they don't come from a wealthy background. (1978).
* When Arnold has to be hospitalized for appendicitis, Phil befriends a potential business associate (Dabney Coleman). The associate agrees to have his daughter share a hospital room with Arnold (because she has to be hospitalized as well, for tonsillitis), but he changes his mind when he learns that Arnold is black. (1979)
* Willis is accused of burglarizing a neighbor's house and stealing her watch. (1979)
* Kimberly's new boyfriend sets up a double date with Willis and his sister, but he revolts when he discovers that Willis is black. (1980)
* Willis joins a street gang against Phil's wishes and ends up getting arrested. (1980)
* Phil develops amnesia after being involved in a car accident. (1980)
* Arnold and Dudley befriend the owner of a bicycle shop (Gordon Jump) who attempts to seduce and molest them. (1983)
* When Arnold is offered drugs on the playground, Nancy Reagan comes and speaks to his class about drugs and pushes her "Just Say No" campaign. (1983)
A Different World -
* Freddie almost becomes a victim of date rape, until Dwayne saves her. (1989)
* Dwayne and Ron get into a fight with students from a rival college who yell racial slurs at them. In a nod to Rashomon, the students tell an officer different versions of the events that occurred. They also argue over race relations. (1991)
Family Matters -
* Laura's locker is spray-painted with racist graffiti. (This plot element was chosen while attempting to increase awareness for Black History Month.) (1991)
* Urkel drinks spiked punch at a rooftop party and almost falls from the roof. (1991)
* Eddie is beaten up by a street gang, after the gang vandalized Rachel's Place. (1992)
* Eddie is the victim of racial profiling when he is pulled over by white policemen in an upscale neighborhood. (1994)
* When Laura gets assaulted outside of school, a guy at school offers Laura a gun; Urkel tries to stop her. (This is one of the most serious episodes of the series; the only comedic scene featuring Urkel and Carl performing a magic trick (in the opening gag). It even ends with a message from Jaleel White about guns.) (1995)
Family Ties -
* A business associate of Steven's makes a pass at Mallory and is urged to seek professional help. (1983)
* Elyse's brother Ned (Tom Hanks) has a severe drinking problem. (1984)
* Alex uses pep pills to get enough energy to keep up with his schoolwork. (1984)
* Alex's friend Greg dies in a car accident. (1987)
* When Jennifer writes a book report on Huckleberry Finn, she receives an F and is threatened with suspension because the book is banned by the local school board. (1988)
* When a black family moves into the Keatons' neighborhood, their house is vandalized with racist graffiti. (1989)
# The Fresh Prince of Bel-Air -
* Will and Carlton fall victim to racial profiling while driving a family friend's car, and are arrested. (1990)
* Will's mother refuses to support her sister's being engaged to a white man. (1992)
* Carlton is hospitalized after taking amphetamines he finds in Will's locker. (1993)
* Carlton loses his virginity to the woman of his dreams, but he feels violated when he learns that the woman is married. (1993)
* After Phil is ordered by his doctor to cut down on fatty foods, he cons Will into sneaking him food. Soon after, Phil has a heart attack and Will blames himself for it. (1993)
* Will and Carlton pledge a black fraternity, but Carlton is victimized while pledging for being a "sell-out". (1993)
* Will's father (Ben Vereen) reappears in his life only to abandon him again. (1994) [episode "Papa's Got a Brand New Excuse"]
* Will and Carlton are robbed at an ATM and Will is shot. While in the hospital Carlton buys a gun for protection. A sub-plot revolves around Carlton blaming himself for Will's shooting. (1995)
Girlfriends -
* An old college mate visits the ladies. When Joan brings up the past and accuses her former college mate of stealing her old boyfriend, the woman revealed that she caught AIDS from him.
* Toni cheats on her her boyfriend with a rich doctor and catches Chlamydia from him.
Good Times -
J.J. is recruited into a gang and is shot in an altercation between his gang and rivals. (1974) [actually Mad Dog was the one who shot him,there was no actual gang fight]
James is killed in a car accident while working in Mississippi. While the kids mourn his death, Florida is curiously upbeat. (1976)
J.J. announces that he is going to marry his girlfriend Diana. When both sets of parents disapprove, they run away and plan to elope in nearby Indiana, where the marriageable age is lower. What J.J. doesn't know is that Diana is addicted to heroin, and J.J. is crushed when she runs off into the night, desperately wanting a fix. (1976)
Michael is recruited into a gang and Florida saves him by going down to the gang's hangout. (1977)
In a four-part episode, Wilona and the Evanses discover that their neighbor Penny (Janet Jackson) is being physically abused by her mother (Chip Fields). After they confront the mother, she abandons Penny and Wilona pleads with a social worker to be allowed to adopt the girl. (1977)
Keith turns to vodka after pressures of unemployment, then he accidentally slaps Thelma.
Wilona is reluctant to talk to Penny about sex until she is almost raped. (1978)
Penny's mother hires a man to seduce Wilona and frame her as an unfit mother. (1979)
Wilona's ex-boyrifend comes back into her life asking for another chance, while secretly sexually harassing Thelma.
Growing Pains -
* Carol's boyfriend Sandy (Matthew Perry) dies after a drunk driving accident. (1989)
* Mike receives preferential treatment from his boss (Dick Van Patten) because he (unlike his coworkers) is white. (1988)
* Mike and his friends are offered drugs at a party. At the end of the episode, Kirk Cameron directly addresses the audience and warns them of the dangers of drug use. (1987)
Hangin' with Mr. Cooper - Earvin falls in love with a girl whose brother is a member of a gang, whose violent ways lead to her death. (1995)
Happy Days -
* Fonzie's African-American friend, Sticks, joins Richie's band. When they perform at Arnold's, no one else shows up due to racism against Sticks. (1975)
* Richie tries to convince Chachi not to join a gang. (1978)
* Joanie is nearly raped by one of her students. (1984)
# The Jamie Foxx Show -
* When Jamie's "li'l homie" Nelson gets hit in the eye by a schoolyard bully, Nelson purchases a gun. (1997)
* Helen gets agoraphobia after she is mugged.
The Jeffersons -
* Florence contemplates suicide. (1976)
* In a flashback episode, Lionel considers looting after Martin Luther King is assassinated. (1980)
* When Tom is invited to join an organization he brings George along to the meeting. Unbeknownst to Tom, it is a KKK meeting. While yelling at George, the meeting's leader collapses and George revives him using CPR. As he is being taken to the hospital, the man's son tells him that George saved his life. The racist leader replies: "You should have let me die." (1981)
[this episode was a trip]
Roseanne -
* After Darlene notices bruises on Jackie's back, Roseanne finds out about the bruises and discovers that Jackie's boyfriend Fisher beat her up. When Dan finds out, he punches Fisher, and gets arrested. (1993)
* Roseanne and Jackie must deal with their abusive father's death. (1993)
* Roseanne's stress at work turns bad when she spanks D.J. after he steals her car. (1994)
* After Darlene's wedding, Dan suffers a heart attack, and is saved by D.J., who performs CPR on his father. (However, in the final episode, Roseanne reveals that Dan did not survive the heart attack.) (1996)
* Roseanne makes Dan go on a diet after his heart attack. After getting caught eating unhealthy food not on his diet, Roseanne and Dan have their worst fight ever — causing them to temporarily separate.
Sesame Street
* Big Bird and the rest of the cast must deal with Mr. Hooper's death. (1983)
The Wayans Bros. –
* Shawn gets hired for a job in an office and later learns that he was only hired so that the company could fulfill its criteria of raising the number of African Americans. (1998)
* Marlon is offered marijuana by a popular actor. He smokes it during an audition for a film, and he is turned down because he was high through the process. Shawn and Marlon both give serious messages at the end of the show. (1999)
What's Happening!! –
* Shirley lands a job as a secretary but later learns that she was really hired as a token black employee. (1977)
* Dee can't accept the idea of her father marrying someone other than her mother. (1977)
* Dee loses a spot on the cheerleading team to her less qualified white friend because of the school's racial quotas. (1978)
What's Happening Now!! –
Dwayne starts dating a nurse from El Salvador, but he later learns that when she returned home, she was killed when fighting erupted. (1987)
WWE RAW – The Owen Hart and Eddie Guerrero tribute shows in 1999 and in 2005, respectively. WWE Friday Night SmackDown! also had a tribute show to Guerrero as well.