Films:
Akira (the film is in exactly the same art style as the manga, which is even more incredible)
All Hayao Miyazaki films, but especially
Nausicaa of the Valley of the Wind
Howl's Moving Castle
Castle in the Sky
Princess Mononoke.
Many of the other films released through Studio Ghibli are also quite good, but the best has to be Grave of the Fireflies.
Origin - Spirits of the Past.
I'll probably think of some more later, but these are the films that I like enough to have them on my hard drive.