You can't be a film buff...

...cinephile, or cineaste if you categorically refuse to watch any particular kind of film. Or films with any particular rating. Sure, you can say you like movies or whatever, but you're not a true lover of the art form if you haven't seen the classics (or if you've only seen edited or "clean" — meaning chopped up and ruined — versions). Sorry.

(Obviously, if you've chosen to not watch some kinds of films or those with any particular rating, the world of film buff-ery may just not be for you. If you've made that decision, that reality obviously isn't abhorrent to you.)