For some reason, I can't think of many particular scenes -- but here are some of my favorite funny movies/television shows:
Monty Python (Holy Grail -- shrubbery, Sir Robin's minstrels, Black Knight especially)
Black Adder (BBC series)
Napoleon Dynamite (especially Napoleon's dance and wedding scene at end)
Galaxy Quest
Chef! (BBC series)
Hitchhiker's Guide to the Galaxy (BBC series)
Airplane movies
First two Police Academy movies
Caddyshack
Foul Play
Young Frankenstein
Blazing Saddles, negro spirituals scene, it's twue, it's twue (hate beans scene)
Spaceballs
Get Smart
Original Dick van Dyke Show
Naked Gun
Skeet Surfing scene, Top Secret!
Real Genius
The Court Jester (especially Chalice from the Palace scene)
Arsenic and Old Lace (Teddy digging the Panama Canal)
The Tick (animated series)-- Especially the Heroes Retirement Home episode with Living Doll -- I'm full of tinier men!
Stripes -- heavily-armed recreational vehicle
Caddyshack
Fawlty Towers
Murder by Death ... It could never be re made these day too unPC.
We took MY grandma to the same movie and she never forgave us because of the snake pit scene!!
When I saw Raiders the first time, I about lost it when Indiana Jones shoots the sword wielding Arab instead of it turning into a big fight scene.
Quite a list.
Do you ever watch "Robot Chicken" on adult swim (Cartoon Network)