In the last month I've seen Matrix 2 and X-Men 2, and both were far better than I was expecting. Not only that, they were both action movie sequels.
Bad movies I've seen in the cinema? Not many come to mind, because I usually only pay to see a movie when I'm sure it won't be too
bad. A few that I'm reminded of from reading through this thread are the last two Batman movies, Godzilla, Star Wars Episode I and II (And for some reason, I'll still want to see III in the theatre too,) sitting through three hours of The Two Towers because I figured that I should see a LOTR in the theatre while I still could and The Mummy Returns (TWICE
I've turned down going to see Scary Movie, Independance Day, Austin Powers 2 and Goldmember, Resident Evil, Street Fighter, Mortal Kombat and more in the past. My friends have a shitty taste in movies.