Blackadder (all five, plus the specials).
The Vicar of Dibley
The Red Greene Show
Red Dwarf
Brittas Empire
Fawlty Towers
The Thin Blue Line
Three's company
When monty python came out I was about 21, all my friends thought it was hilarious, but to this day I just don't know what the hell it's all about, (apart from the parrot sketch I thought that was brill)
Monty Python was one of the best shows ever, but technically its a stretch to call it a sitcom...it was really a sketch comedy show. But it was so good maybe it belongs on the list anyway.
You're not alone in not caring for it though, kev. My wife and I took some neighbors to the Python live performance film (Monty Python Live at the Hollywood Bowl-1982) and they were stone faced throughout while we were rolling in the aisles.
(One of my favorite jokes was in the film and never seen on the series. Playing a couple of Aussies, two Pythons agree that Australian beer is superior to American beer. American beer, they claim, is like making love in a canoe---f***ing close to water.)