Some suggestions:

Not really sure what to tell you. I hate it when I have to recommend something to someone and I can't think of a single thing. Here are the comedys I own and their ratings.

1941 - PG
Austin Powers 2 - PG-13
Austin Powers 3 - PG-13
Back to the Future Trilogy - PG
Blazing Saddles - R
Ed Wood - R
Ghostbusters - PG
Gremlins - PG
Gremlins 2 - PG-13
The Incredibles - PG
It's A Mad, Mad, Mad, Mad World - G
MASH - R
After Hours - R
Monty Python and the Holy Grail - PG
Monty Python's Meaning of Life - R
Animal House - R
Pee Wee's Big Adventure - PG
Dr. Strangelove - PG
The Terminal - PG-13
Who Framed Roger Rabbit? - PG
Young Frankenstien - PG

Maybe that will help? Anyone else have a good suggestion?