Tron:Legacy
I,Robot
Independence Day
All (apparently) considered bad movies, all I like quite a bit.
Dutch starring Ed O’neill.
Beyond the Valley of the Dolls
Star Wars (runs to hide from the angry mob of geeks now currently out to get me.)
BTiLC is a wonderful movie, and the last great thing John Carpenter did.
Roadhouse
The Fifth Element. It’s clear that none of the writers had any clue about, well, pretty much anything they were writing about, and I’m not sure anyone involved with the movie really knew what science fiction is. But it was just so much fun. I think that Mila Jovavich had a lot to do with that.
Sgt. Pepper’s Lonely Hearts Club Band. Just for the sheer cheese of it.
As we MST3K fans know, there can be a LOT of fun in knowingly watching bad movies.
Twister, just to see Helen Hunt in that tight white halter that she wears throughout the movie. And for the immortal line “I’ve gotta go… we have cows!”
Dumb and Dumber is a truly stupid move, trash even - but it happened to be releaesed when I was 13, and at the time I thought it was comedy gold. So I can still enjoy parts of it, and still think parts of it are genius (e.g., the tuxedo-cane duel followed by the whack to the back of the knees).
Plus there’s the shot of Lauren Holly’s magnificent…ahem…posterior. Adolescent GameHat killed a few kittens to that brief scene.
I still love this movie. It’s dumb, it’s not a good movie, but there a few good lines - “What’s the soup du jour? ‘That’s the soup of the day.’ ‘That sounds good, I’ll have that.’”
“Kick his ass, Sea-Bass!”
“I’ll tell ya where we’ll go. Someplace warm. A place where the beer flows like wine. Where beautiful women instinctively flock like the salmon of Capistrano. I’m talkin’ bout a little place called… (silently) As-pen.”
So dumb, but this movie was the movie of my awkward adolescent years. It’s stupid but I still love it.
Johnny Mnemonic.
Independence Day.
*The Langoliers *(TV-movie of a Stephen King novella)
Xanadu
The Manitou, a really cheesy 1970s horror movie that I absolutely love.
Anything about dance (preferably ballet) and/or gymnastics! Ugh, “Center Stage,” “Stick It,” etc.
The message in Flashdance (“never give up; follow your dream”) is a bit sophomoric, but the movie is entertaining as hell! 
There was an episode of Married With Children where they were all in a video store to find movies to rent, and Al Bundy looked askance, doing a double take, seeing a big display of “Dutch” videos - on sale, extra extra cheap! 
predator
Harold and Kumar go to Whitecastle
Man on Fire
Have to add 13th Warrior, really enjoy that one!
Grandma’s Boy. It’s awful. Really, truly, deeply awful. I’m talking 18%-on-Rotten-Tomatoes-awful. And yet, there’s something about it that both my husband and I love, in a completely unironic fashion. And apparently, we’re not alone: the audience rating on RT is 85%. The first time I stumbled across it on TV, I watched for a minute, wondering “What the hell is this, anyway?” Ended up watching the whole thing. Next time I saw it, I made my husband watch it. He was also mystified, yet captivated. Now, we watch it whenever it comes on, which seems to be all the time. And I still don’t know what the hell it is.
Starcrash
Lazerblast.
Eurotrip.
Dumb and predictable teen comedy, but it’s just so… much… fun.