to add, this is one of my favorite letterman moments <object width="425" height="355"><param name="movie" value="http://www.youtube.com/v/glvGfQnx3DI&rel=1"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/glvGfQnx3DI&rel=1" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed></object>
My biggest one is more general than those listed. When Directors especially Steven Spielberg turn a great movie into crappy one by not trusting the audience and insulting the audience. Saving Private Ryan is a great example. The move was great(except for the framing device of the grave scene.) That crap is only there to show the audience they are supposed to feel emotional. I don't need some director telling me what I should feel. Show me a great story, and trust me to feel the appropriate emotions. If the story was good and told in a good fashion I'll feel the emotion. Spielberg crafts good stories, and is a master at setting things up and making most of the movie, but his heavy handed style always takes me out of the story and annoys the crap out of me. Outside of that I agree with a lot of the pet peeves already mentioned. I will mention one more. A moment when a character who has been feeling bad, suddenly discovers love, or some momentous event, and is outside in the rain with their arms outstretched, just soaking it in, and in some particularly overboard situations spinning around in the rain (i.e. see Orlando Bloom in that awful looking film with Kirsten Dunst.) I saw the preview of that, and wanted to vomit.
When there is a character in a movie who does a lot of cussing and screaming when they're speaking to somebody. Like there not capable of speaking at a normal tone or without cussing so much. For example that chubby kid on Super Bad.