Married..with Children (1987-1997), which skewered the Reagan-Bush Era obsession with "family values" by presenting a heterosexual nuclear family in the most unflattering light possible. He played sarcastic son Bud, who, in later seasons, developed an amazingly muscular physique.
After Married, David played gay characters in Get Your Stuff (2000) and in Killer Bud (2001), and in Ten Attitudes (2001), he played "himself," not gay but on the gay dating circuit (for a sleazy reason).
In 2008 he was cast as the lead in The Gay Robot, a pilot for a tv series about...um, a gay robot. The project was never filmed, but the script might have been tweaked into the movie Robodoc (2009)
In his web series Star-Ving (2009), he plays"himself" as a has-been, starving actor whose only source of income is a sleazy porn shop. There is a deliberate gay subtext in his relationship with his best buddy, Corin Nemic (another "has-been" actor from Parker Lewis Can't Lose), plus a lot of nudity (mostly in a failed attempt to demonstrate how "ugly" the extremely attractive Faustino is).
According to his tweets, David is heterosexual but a strong gay ally.