I don't mean to be replying to every post on this thread--I guess I love a lot of books--, but I'm going to have to recommend these in particular for people who don't usually read.
I had this friend in college who had never read a book of his own volition. He wasn't the sort of person who was proud of the fact, he just thought books were boring and had trouble getting through them. This horrified me, as somebody who had a collection of some 500 books or so at that point (almost all of them read). Anyway, he read Hitchhiker's Guide to the Galaxy and then Catch-22, and he was hooked. He's been a reader ever since.