Zakynthos
This island is known for being the most beautiful island in Greece, and after going there once I'm only to 'back-up' this saying because this place is truly amazing! Zakynthos is a part of the Ionian Islands, and is known for having the best beaches around. Not only that, the place is surrounded by sea-turtles, which for some may seem a little 'uncool', but to many is amusing. When I went there for some years ago I was actually swimming above a sea-turtle for a long amount of time. But don't worry, they're usually keeping distance because they're even more scared than you are. Another thing about Zakynthos is that they have a great night-life. The town has many night-clubs around and appearently great music! So if this is what you're looking for, you definitely won't get disappointed. But stay away in the winter! (*brr)