Cruises rock.
We've been on Carnival and Royal Caribbean. Carnival seemed a lot more of a party ship, tons of younger half naked girls dancing all day around the pool, getting drunk and passing out on top of each other.
Royal Caribbean was a nicer ship, better food and just an overall better experience.
Royal Carib was a little more plus their daily charge was more.
Also, bring your own bottles of booze in your luggage..