Batman: The Animated Series
From Superdickery
Quite possibly the greatest cartoon of the last twenty years, and the greatest thing involving Batman other than Legends of Batman, Batman: The Animated series was an animated version of the Dark Knight's various adventures in Gotham, as he tangled with villians as well known as the Joker to previously obscure ones like Ra's Al Guhl.
The show won numerous awards, and helped to spawn the DCAU, an animated counterpart to the DC Comic Universe. It also spawned two spinoff movies, Mask of the Phantasm and Sub-Zero, both believed nearly universally to beat out their live-action counterparts in quality.
The show had two indirect sequels, Batman Beyond and Justice League. There's also The Batman, but most fans of B:TAS think it sucks.