Paul Simon—Graceland
This is my vote, or at least one of them. Why? Well, for starters, because it's a great album without a single bad song on it. It's also pretty varied in mood and style and the arrangements are fairly complex—all things that would help hold my interest for however long I was on the island. Plus, I've enjoyed it for 25 years and never gotten tired of it so that's a pretty good sign for some island staying power.