Too funny. So many of ours have already been mentioned.
"Yes I'm serious and don't call me Shirley" - Airplane
"I picked the wrong week to stop sniffing Glue" - Airplane
"Make these lights blink in sequence" - Airplane 2
"It turned inside out.....and it exploded" - Galaxy Quest
"Miners, not minors" - Galaxy Guest
"I have one stinking job to do on the ship, it's stupid, but I'm going to do it" - Galaxy Guest (yep, we love Galaxy Guest)
"I've got a really bad feeling about this" - All Star Wars movies

"Even if they get out of the casino, they are still in the middle of the f*&$ing desert" - Ocean's Eleven
"I think we're going in...." - Twister (best use of this one was when DH and I were driving on a highway and someone's toy playhouse had fallen off a truck and was right on the side of the road. I was not looking at the road when DH yells that one out and I looked up just in time to see the small house, LOL).