Kimi ga Nozomu Eien is a good choice.
The problem here is that most animes have magic and supernatural powers of some kind. Those would be quite hard to film,
I guess, if not done by Hollywood.
One thing that I'm sure everyone has noticed is the lack of interested from the American voice actors when dubbing
anime. To be able to act properly so that people will BELIEVE in whom you're trying to impersonate, you, the actor,
have to believe it YOURSELF. These voice actors speak as if they were just reading a script, thus dubbed anime is often
said to be bad.
Obviously Americans are not as interested in anime as Japanese are.
To answer your question, though, an anime that involves guns will be best. I choose Cowboy Bebop.