Engaging, entertaining/thought-provoking, thoroughly well-done Watch at least once..

Horror

• Rec - handheld horror mockumentary, Blaire Witch style, but better executed
• The Lost Boys - good ol' times, light and entertaining
• The Craft - quite dark and disturbing, surprisingly
• Heavenly Creatures - maybe not quite a horror, but definitely disturbing.
• Final Destination - (haha, yeah, it's awesome)
• The Girl - behind the scenes with crazy Alfred Hitchcock
• Ginger Snaps - light and amusing
• The Black Swan - quite dark and twisty

Action (Thriller)

• Gravity - not a loud, action-packed thriller, but a slow, creepy, dead-of-space thriller
• The Professional - entertaining, cute
• Choses Secrètes - dark, twisty, erotic
• Face / Off - hiiiighly entertaining, three cheers for Nic Cage
• Red Cliff - the lives of Asian feudal warlords in opposing factions
• The Transporter - amusing, action-packed

Sci Fi/Fantasy

• Resident Evil (all of them, except 2) - completely absurd, but very entertaining.
• Avatar - Live Action Fern Gully, In Space
• World War Z - great zombie flick
• X-Men Origins: Wolverine (2009) - just a well-done X-Men film. To hell with all these awful Marvel movies, but I did enjoy the Wolverine film as it built up his backstory quite nicely in film format
• X-Men, X2 - finally the screen adaptation this story needed
• X-Men: Days of Future Past (2014)^ - I can't say it's very cerebral (when Marvel tries to do cerebral, it's like Ron dressed up as Hermione - so poorly executed that it borders on offensive), but it is very engaging
• Soylent Green - so over the top, it's hard not to love it
• District 9 - pretty realistic
• Stardust - adorable all-ages high-budget fantasy with acting, plot and dialogue to match the production quality (for a nice change)
• Her - oh it was good, and touched on relevant contemporary issues, but I couldn't watch it twice.
• The Witches of Eastwick - just light, fun, stupid and entertaining. Jack Nicholson is Casanova Satan, so this movie could do no wrong.
• Practical Magic - also a romance. Cute and light.
• Plan 9 From Outer Space - watch Ed Wood around the time you view this, and the movie will take on new depth.
• Harry Potter & the Deathly Hallows part 1 - Harry Potter as I wished it had been all along. Can't say that I'm a fan of the franchise - novel or films - but this movie saw the characters and plot at their peak and led me to understand what some of the fuss was about. Of course, you have to have a marathon of the prior films or books to get up to speed, but it's topical for now, so you might as well suffer through it (lol, jk, it's not suffering - it's at least amusing). I mean, if this is the first fantasy book you've ever read, I'm sure it's gripping, but surely its popularity is only a sad comment on how few people are reading outside of school these days. There are FAR better contemporary fantasy books, which fully explore the implications of the fantastical world, patch up the plot holes, and offer characters that deviate at least a SMIDGE from cookie-cutter stereotypes. "Me JK Rowling. Kids good. Bullies bad. Teacher bad. Snake bad. Teacher and snakes on same side...with bullies." Oh really, JK Rowling?
• Beetlejuice - and then watch the cartoon, because it's amaaaaaazing (as outraged Harry Potter fans riot over my prior comment, though I am an anonymous silly internet person who happens to disagree with them. Come now, we can all be friends. We all like stupid things sometimes, right?)

Romance

• Songcatcher - Well, it was the first time I ever saw lesbians on film, and my grandma recommended it, so that was pretty provocative alone. But it's a good solid romance and the male lead is smoldering and heartily Appalachian. Rich with pathos, but real and not over-convoluted with manufactured drama.
• Indecent Proposal - I've outgrown it, though for a time, it was good.
• Harold & Maude - Morbid teenager falls in love with a quirky old lady and constructs a jag-hearse. Need I say more?
• Chilling Romance - grim hilarity ensues
• Dangerous Liaisons - sinister but strangely romantic tale of sociopaths in love, yet not as direct and linear as it might seem on the surface
• Fingersmith - Sarah Waters does a sort of Jane Austen meets Dangerous Liaisons with lesbians story.
• Tipping the Velvet - Sarah Waters erotic lesbian story set in exotic Edwardian environments.
• Dil Se - intense, guerilla warfare & suicide bombers wrapped up in a musical chick flick
• Excess Baggage - classic Stockholm's syndrome romp. I've outgrown it, though for a time, it was good.
• Love the Hard Way - it's quite long and brutal, but affected my emotions profoundly once. Adrien Brody was so irredeemable.

Comedy

• Zardoz - not actually billed as a comedy, though...
• Night of the Living Dead - not actually billed as a comedy, though...
• Ed Wood - the story of one of history's worst (but highly resourceful) directors
• The Heat - fun with Sandra Bullock and Melissa McCarthy
• War of the Roses - dark, dark, so very, very dark. If you want to have your sentimental emotions obliterated for comedic enjoyment, do this. But in a way, it's sort of romantic.
• Death to Smoochie - it's a little too slow paced for me now, but it has a feeling of old detective movie, and it was pretty moving the first time I watched it, because Ed Norton was so loveable.
• Rosencrantz & Guildenstern Are Dead - deadpan hilarity
• My Man Godfrey - black & white, terse wit, delightfully snarky
• Om Shanti Om - "I will not be...a junior actor!"
• The Disco Dancer - low-budget old school bollywood action-romance-drama
• Johnny Eager
• Clerks 2 - Kevin Smith at his best, imo
• Zombieland - oh it was good, even if you don't like the characters, they're still people you know and accordingly lend credibility and relevance to the postapocalyptic plot
• The Wickerman - not actually billed as a comedy, though...
• Zoolander - the only time Ben Stiller has been tolerable

Drama

• Synecdoche, NY
• The Hours
• Factory Girl
• A Single Man
• Marnie
• Departures
• The Station Agent
• Last Life in the Universe
• Hannah & Her Sisters
• The Man Who Wasn't There
• Miller's Crossing
• Chasing Amy - kind of a comedy, but pretty heavy
• The Waking Life
• Lolita

Westerns

• 3:10 to Yuma (original or remake, both good)
• True Grit (remake)
• The Outlaw Josey Wales
• The Good, the Bad & the Ugly

^pending a place among the re-watchable