In order of which I would take to a desert island. Based on books that I could think of off the top of my head, and that I could see on my bookshelf without getting up off my couch.
The first 25 or so are pretty firm (although I feel a little guilty about having so much Hemingway near the top cut me some slack with those). After that, well, the order is likely to shift on any given day. And it gets downright ugly near the bottom.
And I dont want to hear any crap about literary merit. Im not about to argue that Jurassic Park (69) is a better novel than Light in August (83). Id take it with me first, though. Or, at least, if you asked me right this moment I would.