Mask of the Phantasm's my favorite Batman movie. My primary Batman continuities will always be the Silver and Bronze Age Batman and post-Crisis to Zero Hour Batman, but BTAS/the DCAU is easily third.
I read The Killing Joke and never understood the why it was considered so great.
Prior to 1988, the absurdity of Batman and the Jokers' never-ending cyclical relationship hadn't ever really been deconstructed before and also the Joker hadn't ever really been given much of a motivation or an origin. TKJ changed all that and also eliminated Batgirl (back when continuity still mattered) all in one fell swoop. And on top of that it's a technical masterpiece (my personal favorite bit's the panels of rain that bookend the story and symbolically bring the main theme full-circle). And finally, in the late 1980s/early 1990s, DC took full advantage of both the popularity of Alan Moore and Bat-mania to hype the holy hell out of it (I'm pretty sure that at least a dozen of us in my 9th-grade class had a Brian Bolland Joker t-shirt).
