Stay away from the American version like the plague. The Japanese original is full of wonderful harsh language and crude humor that cannot be shown to American kiddies. Sanji, for example, is a chain smoker--not a lolipop afficianado.
If you don't speak Japanese and can read subtitles quickly, the best place to go for One Piece episodes is Kaizoku Fan Subs http://www.kaizoku-fansubs.com/torrent/index.php.
I just got back from Tokyo and saw the latest movie in a theater. Sure, I couldn't understand a word of it, but I got the basic idea and still had a few laughs.
Adventure, comedy, more adventure, lots of fighting, insults, lots of eating, even more adventure, and virtually no romance. And more eating.