Since I'm going to cut out shows that started in the 80s, my list would be:
1. Weird Science - when announced I never expected it would be as good as the movie, but I'm glad I was wrong. Very funny show. Incredibly enjoyable, and the vast majority of episodes are fantastic. It suffers in its final season like most sitcoms but it's still a great show. Always wished it would've gotten a full release on DVD or bluray, although I did hear it did on DVD in australia. Was my go to show throughout high school.
2. Seinfeld - what else is there to say. A classic and then some.
3. Get a Life - often forgotten fox sitcom starring Chris Elliot. Some wacky episodes in this one.
As much as I like Charlie Sheen in some of his other shows, I just did not like Spin City after he replaced Michael J Fox. It's not that he wasn't as good, it's the fact that so many people left the show. Several writers, the producer, and several characters left the show and were written out for the last two seasons.