AmandaJR
Money List Winner
Used to love watching The Good Life 
I think that Only fools and Porridge are the two best there has ever been and ever will be
For me personally a good sitcom must have excellent characters. Del Boy and Fletcher are absolute examples of this, superbly written and almost lifelike, even though they are caricatures.
My other favorites are Father Ted, The Thick of It, Black Adder, Step toe and son for example are all based around superbly comic characters and amazing writing.
I think any good British sitcoms are a very rare beast these days and the vast majority of things on these days (im only 36) is garbage.
Apart from Father Ted Crilly, Malcolm Tucker, Partridge, Brian Potter, Rab Nesbitt and a few others. Nothing comes close to the rouges and scoundrels created in the 60's, 70's and 80's.
Dying art form in the UK
EDIT - I have just remembered Peep Show and the in betweeners. Both fantastic
All a bit politically incorrect these days. Saw a couple of episodes of on the buses recently. I don't remember it being so sexist. I suppose when I watched it at the time it was first aired it was the norm.
Outnumbered. Some of the early ones when the kids were small were unscripted.
You could add Mind Your Language to the list. So racially incorrect it's another that'll never (rightly) get aired again. I also don't remember On The Buses being quite so sexist but as you say sitting watching it at the time you're impervious to it all