My top 10 in order of release year:
Snow White and the Seven Dwarfs 1937
Pinocchio 1940
Lady and the Tramp 1955
The Sword in the Stone 1963
The Jungle Book* 1967
Robin Hood 1973
The Rescuers 1977
The Black Cauldron 1985
Aladdin 1992
Mulan 1998
*Most favourite
So old Disney still wins for me though Pixar only made excellent movies so far (my favourite is still Monsters Inc.) and though Pixar and Studio Ghibli are today's best animation studios.
Pixar saved Disney because ex-Disney worker and huge Disney fan John Lasseter decided to continue the collaboration.
EDIT: To make clear why I just compared Disney to Pixar: In my opinion Pixar IS the new Disney with regards to featured animation movies, I think Disney itself has no real animation studio anymore, but old Disney still wins for me.
