You have no right, however, to be a complete and utter jackass and ruin the experience for other people in the theater
Like many of you, I went to see The Hobbit this weekend. Unlike many of you, though, I had the utter misfortune to see it while in the same theater as a rabid Tolkien fanboy who did not shut his fat gob the entire movie. He had something to say every 2 minutes and loudly complained how Peter Jackson had ruined the Hobbit and Lord of the Rings and how the movies had bastardize the "perfection" that were the books.
Oh and let's not forget all the swearing while in a theater mostly full of children.
I get not liking a movie. I have no problem with someone not liking a movie. I don't like a ton of them myself. But that doesn't give you the right to be a jackass and ruin other people's night.