The Naked Gun.
Watch Out Were Mad (I dont imagine many will know of this)
The Return of the Pink Panther.
Airplane.
Monty Python Life of Brian.
Hot Shots (just about)
In the new and old version, I can't do anything but break down into fits of laughter during Springtime for Hitler (have to say I prefer Gary Beach DeBris playing Hitler ahead of LSD)
Pink Panther: A shot in the Dark (I think), purely for the "does your dog bite" line. Best line of all time.
Airplane never fails to make me laugh and more recently Team America.
South park the movie
Spinal Tap
Life of Brian
Blues Brothers
Kindhearts & Coronets
Anchorman
Old School (just for the wedding singer right at the beginning)
Duck Soup - the bit with the mirror slays me everytime