I suppose if we’ve exhusted movies we could really go out on a limb and start a thread for first lines of books 
“I’ve got a call on the other line…Call me back Ishmael.”
Stolen from The Simpsons
Okay, here’s a good opening line from a fairly recent film:
“AAAAAAAAAAAAAAAAAAAAAAAAAAUUUUUUUGH!”
Any guesses?
Lethal Weapon II?
if not, let it continue, if so:
“this is a routine pursuit…”
This is far too easy, but it’s the only one I know verbatim off the top of my head:
“Once upon a time, in a faraway land, a young prince lived in a shining castle.”