Fight Club and The Princess Bride would be my favorites, based on a book or not those are just plain my two favorite movies. Period.
You can probably list most, if not all, of Crichton's films here. The books are good enough that even a decent film adaptation makes a good movie. Sphere, Jurassic Park, Congo, Eaters of the Dead / The 13th Warrior, Rising Sun, Timeline, Disclosure... all good. The Andromeda Strain was very good, I heard about a recent film but I'm talking about the early 70's one. A couple of the Tom Clancy books got decent movies, but they got some crappy movies too. Hunt For the Red October was easily the best film of the bunch, but some of the better books got the worst movies. Shame, that.