For tv.. As a kid it was Mick and Montmorency. Growing up became The Goodies & Monty Python, Spike Milligans "Q" series then Fawlty Trowels which is timeless. All the Black Adder series and odd programmes of the Young Ones etc. Also Michael Bentines it's a square Wold which I used to go to the beeb to see being recorded and where I was when Kennedy was shot... To prove we all remember where we were when we heard that news.
For American sit com.. I love Lucy & Bilko from the 50's. Frasier is a brilliant follow on from Cheers, occasional episodes of Friends (still).
I'm sure there are more.. I just need to see a few more posts here to remind me