I have yet to find an actual favorite movie since I've seen and liked so many, so I'll just put down the ones that made it to the top in my opinion. This list is in no order, just the movies that pop up in my head as I type this. You may not of heard of these movies as I am in love with international films. As well as those that were imported and published here.
Howl's Moving Castle.

This movie was directed by Hayao Miyazaki and is a Japanese animated film made in 2004. This is known as one of Ghibili's/ Miyazaki's masterpiece.
I've always find myself coming back to this movie whenever I had the
time to do so. Out of all the Studio Ghibili's movies I'd say this one
is the best. If you've never seen one of their masterpieces I suggest
you do so now.
The Host

An international korean horror film in 2006. Even though this movie is in the horror genre I found it quite hilarious, with the main character's clumsiness avoiding this huge monster that attacks. It's about a family running away from a monster generic but it gets to be in my top 3 obviously.

Cowboy Bebop: The Movie

This here movie is what turned me into an anime enthusiast. Cowboy Bebop basically helped grow the anime audience in America as well as casting the perfect voice actors for this series. It's action packed scenes and engaging plot made this a great start for those interested in the anime genre. This movie was based on the running t.v. series.