This is impossible, too many good ones: Go the Distance, Be Prepared, Part of Your World, Kiss the Girl, That's How You Know, ect.
So I'm going to cop out and pick two:
'I Won't Say I'm In Love' from Disney's Hercules. Great harmony and lyrical quality. It's feel good and authentically Disney at it's core.
'When Love Is Gone' from Muppet Christmas Carol(AKA the best Christmas movie that has ever been and will be.) It is one of the most un-Disneylike songs that Disney ever produced(Disney in fact got the song pulled from the film and it was only through Jim Henson's demands that it was placed on the extended directors cut.) So I doubt most people have ever even heard it, as doing so requires either specifically searching for it, or purchasing the Muppet Christmas Carol on special edition DVD/blueray.
But it is one of my favorites. It is beautifully sad, and I can't help but to tear up when Michael Caine starts to sing along with her. And at the same time it adds so much to the character of Scrooge. It make's him understandable, it helps to bridge that gap to explain how he got where he is.