These two words have the same meaning. However, the usage varies depending on the region.
USA: The standard word is 'movie'. 'Film' is known, but used far less often.
I find it intriguing that Kelakio says that 'film' is US slang, whereas Johnny sees the word as pretentious if used by Americans (as is often the case with British terms!) . It would be interesting to find out who is right here. Can any other Americans shed any light on what the term 'film' suggests to them?
Britain: 'Film' is the standard word.
British people are all aware of the word 'movies', and are aware that it is an American term. 'Movies' is sometimes used in the UK, particularly with reference to US cinema.
Australia: Both words are used interchangeably.