I have read most of their works. I have always been a big fan of fantasy in part because it allowes me a bit of escape, but also, many of the works actually take the events of the world and work them into the story. I think the Lord of the Rings series would be the best known for that.
Glad to hear you've read them! I understand the whold "escape" thing. I actually found my biggest escape while reading the Dragonlace series was in all the amazing dreams I'd have. Soaring on dragons, fighting, running through the crazy world trying to escape...ahhhh... I've never read the Lord of the Rings series, though. I've been told my numerous people that the books were very slow and boring. So, I never got around to them.