In my opinion, what you should say is show them the upside of the movie. This is by comparing the entire new things that the movie shows concerning the vampire and werewolf species. An example is glittering in the sun and also the vivid transformation of a human to a vampire.
Love what you love, and if people dont agree with you, then just ignore them. But, personally, for people who don't like twilight, I mention that though the movies didnt look that great (in my opinion), the books were actually pretty decently written, up until the last one anyway (again, just my opinion).