Here, I'll start:
I Hate: Drag me to Hell, Pretty Woman, Precious, Fight Club, Dragon Tattoo, American Beauty, Notting Hill, 4 weddings and a funeral, The Deep End, Mystic River, Hitch-hiker's Guide to the Galaxy, Boondock Saints. I hate feel-bad movies and anything pretentious in general. Didn't understand the hype around Artist, didn't really like Avatar either apart from the graphix.
I Love: Drive, most Guy Ritchie films(Snatch, Rocknrolla, Sherlock holmes 1/2), Men in Black, District 9, Chronicle, Kick-Ass, The Ring, Woman in Black, Paranormal Activity, LoTR, almost all the harry potter films, Forrest Gump, Saving Private Ryan, Inbetweeners movie.
(most of these films are hated either by critics, or mainstream audiences, or imdb, or the internet or the Awards)