I can't do a Top 50, it's way too annoying to figure out if this movie should be placed 42nd and this one at 38th place. So here's my top 10:
10) The Iron Giant: I loved the 50's vibes, Bird's a genius.
9) The Lion King: Disney's Macbeth is my favorite among their golden period in the 90's.
8) Ratatouille: Should be on any top 10 list for the ENDING ALONE.
7) The Incredibles: First movie where Pixar showed me that they can do more than kiddy fare.
6) The Land Before Time: Before all the trashy sing-along cash-in sequels, there was this gem. Go Littlefoot!
5) Spirited Away: Miyazaki's most complete movie IMO. The animation, music, story is just something else.
4) My Neighbor Totoro: This movie is the best kid movie ever. I'm lucky enough to watch it with my eight and two year old sisters (what are the chances? :lol) They love it too.
3) Wall-E: Magic that told a love story between two inanimate objects better than most romantic movies. I feel sorry for people that focus in other messages and can't get that.
2) Only Yesterday: Saw this the other day again. Yes, it can be totally done in real action, but animation actually improves on reality. That's not something that can be said often or taken lightly.
1) Nausicaa of the Valley of the Wind: Yes, shut up, I know the manga is better. Always my childhood sentimental favorite.
4 Ghibli, 3 Pixar, 1 Bluth, and 1 Disney, and 1 WB. Sounds about right to me.