Some of the TV show is a bit hit and miss but it always was -- if you know any comedy sketch show as it were that was wall to wall hilarity for 4 series (some 45 episodes, each up to 30 minutes a piece) then please please please do share with the class. Alternatively there was a nice compilation film called And Now for Something Completely Different which was somewhat panned at the time for being just a compilation of things people had likely been watching on their TVs for the last however long (rather unfortunate given the name) but today serves as a decent compilation.
The standalone films are still spectacular and probably will be for generations to come. We can probably get in a nerd fight over which is best but I will watch any of them if given half a chance.
I might also suggest their live at the hollywood bowl... I guess it would be called a special these days. The audience participation/interaction stuff alone is something I did not expect from them, and as I sit here there are maybe 5 comedians I know of that do it as well or better as part of the act (if you count dealing with hecklers there might be a few others that are as sharp).