In no particluar order:
Porky's - Scene in principal's office (That takiwacker had a mole on it). The actors deserve an ocscar for just getting through the scene.
Ferris Bueller - What did you kick me for? Where's your head (question/answer repeated several times)
Vacation - Chevy Chase running acrosst he desert and the Indian commenting to the other "What an Asshole"
Animal House - Pick your scene, my favorite is the horse in Dean Wormer's office.
Its a Mad World - Again pick your scene, Ethel Merman slipping on the bannana peel at the end is great.
Sinefeld - Many favorites here, How bout Kramer throwing his money on the table after only being out of the room for a minute to announce he is out of the "contest"
Arthur - Sir John Gielgood (sp?) telling Liza Minella that normally one would have to go to a bowling alley to meet a woman with her class
Cheers - the thanksgiving show food fight
All in the Family - An episode where Archie and Meathead each remember their own versions of two repairmen coming to fix the refrigerator
King of the Hill - the one where they burn down the firehouse and each character has his own version of what happened
The Simpsons - Many again, the episode where Homer gains weight to stay at home and buys the Moo Moo, because he doesn't want to look stupid.
The three stooges - "A plumbing we will go". Curly finding the elecrical wires in the "pipe" and telling Moe. "Get em out of there knumbscull". Later when
water is coming out of the stove, lighting, etc the cook says "This house sure gone crazy"