Okay, I love Mulan a LOT (Shan Yu is so cool), and I'm quite partial to Hercules (though I've not seen it in some time, so that may or may not still be the case), but my favorite Disney movie is definitely the Black Cauldron. Because, I mean, have you SEEN that ****? The bad guy is a goddamn undead conjurer of evil. And it's been a while since I've seen it but when I was really little I loved the hell out of it. Almost entirely because of the villain, but still.
Also, if Pixar entries count then my favorite Disney movie is actually probably like Monsters inc. or perhaps maybe Bug's Life...
Also also, if any movie OWNED by Disney counts (and I know it doesn't) then my favorite Disney movie is a tie between almost every Studio Ghibli movie.
Also also also, **** Frozen. It's bad. It's the worst.