I love "The Big Bang Theory". I do not think that I have missed an episode. I have learned things and I have also caught mistakes on the episodes. It is fun. I practically know the lines by heart now - at least some of them. I started a blog on it but I have no viewers yet - at least no comments.
Great question. The '90s had memorable TV shows. I would say Seinfeld, but there's a show I don't see on this page that I feel compelled to mention — Mad About You. It was not only a good show, I think it produced the best clip show (the second one I mean; they had two of them) and the best finale of any show I've watched.