OK, I'll bite. I'll try to keep it to non-revered, guilty pleasure movies
I enjoy semi(?)-brainless rom-coms...so relaxing. So I have a few categories for those:
Cheesy Christmas rom-coms: The Holiday, Four Christmases
Nasty rom-com: The Break-Up
Regular rom-com: Spanglish, Miss Congeniality, The Proposal
Not-Really-a-rom-com: The Intern
Creepy rom-com: The Cable Guy, Little Children (more of a rom-drama)
Sad Rom-com: 50/50, Election
Underrated Apatow rom-coms: Funny People, This is 40
BDSM Rom-com (haha): Secretary
Romantic Drama: The Adjustment Bureau
Some random choices in other categories
Action: Pacific Rim, They Live, most Korean vengeance movies, most Rambo movies (including First Blood), Hancock, Unbreakable (more drama than action), Jackie Brown
Horror: Ravenous, Rob Zombie movies (including the Halloween remakes), Rabid, Dead End
Journalism movies: All the President's Men, Spotlight, State of Play (all good movies so they don't count here. I'm just a sucker for those)
Most Cronenberg movies, especially Eastern Promises
Just about anything with Bruce Campbell
Just about anything with Sidney Poitier
Comedy: I'll need to think about this category. Some random ones off the top of my head - Clerks 2, Keeping Up With The Joneses, The Other Guys, Midnight Run, Planes Trains & Automobiles
Sci-Fi: The Matrix trilogy, Her, All Alien movies (including the Prometheus series), Primer, Looper, Coherence
Foreign Dramas: Amores Perros, Sin Nombre
Sports movie: Goon (and Goon 2)