I recently finally picked up the new Hitchhiker's Guide to the Galaxy book that has all the novels in one volume. I read them once before, but it's been more than 10 years I think and I'm really (re)enjoying Adams sense of humor. FWIW I loved the movie version too. Thought it captured the essence of the novels really well.
If you're looking for another fantasy series, my favorite is the Farseer Saga by Robin Hobb (interestingly, I've never been able to even get through any of her other series) - it's fantasy, but its a very unique world with its own great mythology and "magic" systems. And Fitz is an awesome POV character.