Strictly speaking, I think it’s:
“What is something happens?”
“What could happen to an old-fashioned?”
Dark Star
Yep! Pinback and the alien.
“Each day is better than the next.”
Sorry, I’m afraid not.
Crap! 
“That’s fuckin’ blasphemy. Elvis wasn’t a Cajun.”
I don’t know that line specifically, but it sounds like Buzz, the elevator operator in The Hudsucker Proxy.
I was thinking Jack Lemmon and Shirley MacLaine. I don’t know any other movie that features an elevator operator.
It’s Hudsucker.
The Commitments.
Yes! One of my favorite movies, full of great lines like “Say it out loud: ‘I’m black and I’m proud!’” 
Fully agree. “Hey Jimmy! Last month, I was an unemployed pipefitter. This month, I’m an unemployed jazz musician.” Many great lines in The Commitments.
“Who are you working for?”
“Blockbuster Video, Des Moines, Iowa.”
“Who are you working for?”
“Blockbuster Video, Des Moines, Iowa.”
“Damn! They train him so well.”
“Where you’re wrong and where you’ve always been wrong is that you fight with weakness and begging. We are fighting with strength and we will win.”
Ah well, no-one got this. It is a bit too British I think; Carry on Cleo, and the next line is
“No, no, no; it’s supposed to bite you!”
Here’s another British one, a bit more famous-
Architect: “I have an awful feeling we’re not going to get our fees on this job.”
“It takes awhile to get to know the town.”
“How long have you lived in London?”
“All my life.”
“How come you don’t have an English accent?”
"Hey, I’m lucky to have a driver’s license!"
I was sure this was going to be from A Fish Called Wanda!
The Great Muppet Caper
Correct. I love that scene so much.
Still in play:
“Who are you working for?”
“Blockbuster Video, Des Moines, Iowa.”
“Who are you working for?”
“Blockbuster Video, Des Moines, Iowa.”
“Damn! They train him so well.”
“Just a slight stiffness coming on.”