here are some of my favorites.

hottest state - Jesse: [to William in the restaurant] A lot of bad shit is gonna happen to you. People are not gonna love you back, and if you're serious about becoming an artist, that's the first thing you should learn. And, listen, you're gonna die, okay? Relatively soon, okay? So, that being said, you have nothing to worry about.

playing by heart - i think i can quote almost all this movie by heart 
Keenan: My mind has an endless capacity for useless information.

and from my very beloved tv series:
scrubs
Every one of our parents does some considerable emotional damage; and from what I've heard, it just might be the best part of being a parent.
Go ahead and replace the captain of your brainship, because he's drunk at the wheel!
This is the reason why your headache didn't go away: That's actually pronounced analgesic, not anal-gesic. Sir, the pills go in your mouth
the wonder years
Growing up happens in a heartbeat. One day you're in diapers, next you're gone. But the memories of childhood stay with you for the long haul.
I remember a place...a town, a house like a lot of other houses....a yard like a lot of other yards...a street like a lot of other streets. And the thing is....after all these years, I still look back...with wonder. 

i can go on and on but i'll stop for now

Ladyhawke

Heh, I'm ripping the CD right now.  Can't listen to "Phillipe's Escape" without hearing those lines in my head.

"That's part of your problem: you haven't seen enough movies. All of life's riddles are answered in the movies." Davis (Steve Martin)
Grand Canyon

Not the right scene or character but it was the only one I could find

"Why would I shoot a bloke BANG, then take him to the bloody car and wizz him off to the hospital at a hundred miles an hour? It defeats the purpose of having shot him in the first place." - Chopper Reed (Eric Bana), Chopper

These are really random.  LOL! couldn't find a pic of that scene.

This one just popped into my head that I've always loved...

"Don't be a guy.  The world is full of guys.  Be a man." - Cory (Lili Taylor), Say Anything.