There is no difference in meaning between these two terms. And the usage is not as simple as a straightforward American/British distinction.
As Eltoy has explained, 'movie' is most widely used among Americans, while 'film' is more frequently used in countries using more British English. In fact, he has expressed this so well that I've repeated what he says word for word. Eltoy's words are well chosen:
'Movie' is most widely used among Americans - but that doesn't mean that it isn't used elsewhere in the English-speaking world. Speakers of British English also say 'movie', particularly to refer to popular, commercial 'blockbuster'-style productions.
'Film' is more frequently used by speakers of British English, but it is also sometimes used by speakers of American English, especially to describe more serious, European-style 'art' productions.
In countries such as Australia, which has influences from both US and GB media, the two terms may be used interchangeably.