Oh wow sorry for the late reply >.<
It's hard to pick one, I think it might be Mulholland Drive, or maybe The Mist or 1403...

that's kinda hard to choose, i don't watch movies that often...

I haven't watched a ton of movies...

But I'd have to go between Castle in the Sky or Josee, the Tiger and the Fish.

I'm not much of a movie person. If I had to say, No Game No Life: Zero.

not really a movie watcher to say..

2001: a space odyssey

Anything with catgirls in it

Probably Princess Mononoke, though Terminator, Mad Max 2, 10 Things I Hate About You, The Martian, and The Disappearance of Haruhi Suzumiya are all strong contenders.