Well, I don't know about being well-informed. I'm a bit of a know-all f*%$ all when it comes to many topics. I've grown up with entertainment all my life, I come from a showbusiness family and I've worked in various aspects of showbusiness, but I'm hardly a comedy historian (talk about an unfunny juxtaposition).
I'm with you on Blackadder, Fawlty Towers and I can understand why they liked Yes, Minister (although it never floated my boat, I preferred "The New Statesman" with Rick Mayal).
Dad's Army: One of my mum's favourites. It had great characterisation (often taken off to this day), an excellent cast and was very traditionally British with its humour. Although not amongst my all time favourites, I like the fact it has a placing.
The Good Life: I suppose it's the comfort factor, which I think strikes a nerve with most people who like genuine comedy (in other words not just vicious snipes and dirty jokes). The British love to take the micky out of themselves and the snobbish divide here is testament to this. However, I don't really see why fans of The Good Life didn't vote in "Fresh Fields", "Terry and June", "George and Mildred", "Ever Decreasing Circles" and all the other 30 something to mid-life bland sit-coms. Actually looking at that lot I suppose we got off lightly. They could have had "Butterflies" in there urrgh! (where's the hack up emoticon?)
One Foot in the Grave: The show certainly had its moments, and this came as no surprise to me whatsoever. It has aspects of the tragi-comedy, which is a difficult genre, but is often done very well in the UK. See the feature film "East is East" for example. Victor Mildrew is a well known and well loved character in British pop culture. Again, not one of my favourites, but it's very popular and appeals not only to its own age group (OAP's). It was certainly better than "Waiting for God", which did have its charm.
Only Fools and Horses: I went out for dinner with both David Jason (Del Boy) and John Sullivan (the writer of OFAH). This is probably THE most popular British sitcom and audiences don't want to see it go. Again, you have the tragi-comedic aspect, which makes up its formular. It would have rated amongst my "almost favourites" if it hadn't been so badly tarnished by the too-many-Christmas-special syndrome.
The Vicar of Dibley: I love Dawn French's comedy and Ian Richardson is a great writer, but this never did it for me. I can see its appeal, but it's far from being an all time great.
Porridge: You've got to admire the ambition and originality of setting a comedy in a prison. It resembled the Dad's Army style with a strong cast, a fair bit of loveable characterisation, but with less slapstick and a hint of tragedy at times. I preferred it to One Foot in the Grave, mainly because I think Ronnie Barker is brilliant, but it won't be a DVD set I'll be counting in my collection.
Open All Hours: Featuring both David Jason and Ronnie Barker. In retrospect, where could it have gone wrong! Looking at its placing it didn't, but not my cup of Rosey Lee, if you know what I mean
It would appear that the key to classic comedic success in Britain is to follow these guidelines.
1. Employ Richard Curtis as your writer
2. Employ either Ronnie Barker or David Jason or both
3. Send up the British establishment
4. Get the "comfortable" element with reliable characters
5. Loveable rogues are good (OFAH, Blackadder, Porridge, Dad's Army etc. The Good Life is perhaps the only exception here)
6. cultural divides going, be it between classes or ages (although if you are going to handle racism and bigotry don't go the way of "Love Thy Neighbour", Alf Garnett is even looked down upon now, which is quite ironic)
7. Everything before the seventies isn't funny (no classics from Alan Simpson and Ray Galton "Hancock" and "Steptoe and Son"

)
Red Dwarf: I've given my review of this.
Father Ted: Brilliant, much better than the Vicar of Dibley.