Edited To Add: Two changes: I've added which decade each film came out during; also I've added a line from each film.
80s: 1. You can't have people whose house is burning down saying "Whatever you do, don't call the fire department!" That would be bad. -- Roxanne. slipjig.
50s: 2. Don't you know everyone wants to laugh... / She can't act, she can't sing, she can't dance. A triple threat. -- Singin' in the Rain. theloriest, followed a few minutes later by blubeagle.
90s: 3. I'm Brian Dennehy. -- South Park: Bigger, Longer and Uncut. theloriest.
80s: 4. You are America's best. Make us proud. / Because I was inverted. -- Top Gun. Not guessed.
80s: 5. Jocks only think about sports. Nerds only think about sex. -- Revenge of the Nerds. knowmad.
70s: 6. Sit down. Have a scone. Make yourself at home. YOU KLUTZ! / Where's the fetus going to gestate? You going to keep it in a box? -- Monty Python's Life of Brian. setsuled.
80s: 7. So many social engagements, so little time. / Ray! Now you take that diaper off your head and you put it back on your sister! -- Raising Arizona. greyaenigma.
80s: 8. He prefers East German men. / It's a topsy-turvy world, and maybe the problems of two people don't amount to a hill of beans. But this is our hill. And these are our beans! -- The Naked Gun: From the Files of Police Squad!. theloriest
80s and 90s: 9. No ticket. (Two films! At least, two films I can think of...) -- Indiana Jones and the Last Crusade, and then Dogma. theloriest. (It's two of the three words Silent Bob speaks in the theatrical cut of the film.)
80s: 10. 'Course, there's one good thing about a reactionary President, he's not into health foods. / You've been drinking your whiskey from Kentucky. -- 2010: The Year We Make Contact. slipjig.
80s: 11. I'd hear "Who's that lurking over there? Isn't that Merv Griffin?" / You thought, you thought. Just go. Three years of nursery school and you think you know it all. Well, you're still wet behind the ears. It's not a subdural hematoma. It's *epidural*. Ha. -- The Man With Two Brains. greyaenigma.
90s: 12. Well, first of all, it's because I'm a Beatlemaniac. And second, these sound better. -- The Rock. happyspector.
90s: 13. We hope you've enjoyed our programming, but more importantly, we hope you've enjoyed...life. -- Gremlins 2: The New Batch. theloriest.
This decade: 14. I'm not lookin' for the best players, I'm lookin' for the right ones. / If we play 'em 10 times, they might win nine. But NOT this game. -- Miracle. Guessed by theloriest, who went to high school with an actor in the film.
This decade: 15. Where's his car, dude? / Katie Holmes is a nice, respectable, wholesome girl... and I'm gonna see her boobs. -- Harold and Kumar Go to White Castle. Not guessed. (It was by the same director as Dude, Where's My Car?, so they threw that in as a nod. Both films are freakin' hilarious, by the way...)