1) What's the best tabletop system you've ever played?
AD&D 2E; This is the game that came out the summer before my group of friends entered tenth grade. It was the version of D&D that existed when we were getting our licenses and able to play virtually every weekend. it was the beginning of the first "real" campaign; the one where story progressed from session to session, and the bedrock of the games I'm running now, like 25 years later. So, I'm highly biased. I like the way the rules corrected some "broken" aspect of 1e, like capping fireball and lightning bolt and magic missile. I loved Initiative going from d6 to d10. And the introduction of specialist wizards revolutionized the way the game was played for our group. We've added elements of every edition, before and since, to our game, but we (my gaming group) all still say that the bedrock of our campaign is 2E AD&D.
2) What's the worst?
D&D 4E. When 3E came out, and Gary Gygax publicly said that "This is not D&D," I thought it was hyperbole. The basic tenets were all there. The rules were streamlined. The new stuff was largely ADDED to the game. When 4E came out, and I bought up all the first release books, I understood what it would take for me to say, "This is not D&D." The basic core of the game was no longer present. Key concepts that had been there from the very beginning were just gone. A conscious decision had been made to target a new audience, and as a lifelong player, that was not me. After some effort, we found a number of things we could incorporate into our ruleset, but overall the game was...not D&D. To me.
3) What's the one you've always wanted to play, but never got the chance to?
Until recently, the list was very long. I think that the game I have most wanted to play, though, is Chill. I've run several one-shots and read practically every published book, including the anthology of short stories they published years back, but no one that I know has been willing to run a game.