I have several but some of my faves:
Cave dwellers: (Ator's kneeling) What is Ator sitting on?
Godzilla vs. Megalon: I can fly, I can fly! I can swim!
Future War: Ladies and Gentlemen, Fred Burroughs!
Manos: this is a bughunt man, game ove man, game over! (not in theather but still cracks me up)
Eegah: He knows women and she's gonna want that purse
The quotes may not be exactly right, but ya'll get the idea.