I don't have a favourite of the Disney songs. MAINLY BECAUSE I CAN NEVER CHOOSE JUST ONE!!!!
A few of my favourites include Pocahontas- Colours of the Wind because it is so beautiful, One of us- lion king because me and a good friend of my sing it to each other way to much xD, Mulan- I'll make a man out of you because come on how does this song not come up every day in convosation! and aladdin- Whole new world (its on repeat quite regularly on my ipod).
Disney has one of the most amazing iconic soundtracks that will never die.