ooh, babe made me think of charlotte's web!
milo & otis
where the wild things are (although this is too upsetting/scary/sad for many kids, and probably boring for some three-year-olds, but my boys love it)
the fantastic mr fox
robin hood (the disney movie with the animals)
the sword in the stone
pingu (shorts we watch on youtube, they're like 5 minutes)
the nightmare before christmas
james and the giant peach (fairly scary in some points though, might want to pre-watch)
little bear (episodes of the tv show on dvd/vhs)
my kids also love any older vhs tapes i find at the thrift store that are animated versions of story books, which are super mellow.
oh yeah! how to train your dragon. that is my freaking favorite kids movie ever.
i'm also really excited for when my boys are old enough to be interested in whale rider, because i loved it so much, but i think it's probably more for 8-12 (my boys are 4 & 5.5).