My wife and I are going on our first cruise in June on Carnival's Sensation, and we're excited too! We have heard from friends that if you're on a tight budget (as we are!), getting a cabin with a window is great for the first trip, but after that, if you need to save a few bucks (again, as we do!), its worth it to just get an inside cabin. We are already planning on saving the $$$ on any future cruises we take and using it drinks, tours, ect...
Since you almost HAVE to meet other people on the cruise, we're sure you will have a great time.