1) Sorry, I don't know the answer to this one.
2) Not all the Carnival ships have the waterworks. It is being added to the Fantasy class ships, beginning last year and extending through next year. The Fantasy class ships are:
Fantasy - which does have the waterworks
Ecstasy - which does not have the waterworks yet
Sensation - which does have the waterworks
Fascination - which does not have the waterworks yet
Imagination - which does have the waterworks
Inspiration - which does have the waterworks
Elation - which does not have the waterworks yet
Paradise - which does not have the waterworks yet
The Dream will have the waterworks, but the Dream is still being built.
3) The family friendly lines are Carnival, Disney, Norwegian and Royal Caribbean. Given your interest in the waterworks, I would suggest also looking into Royal Caribbean's Freedom class of ships (Freedom of the Seas, Liberty of the Seas and Independence of the Seas). All three have what is called the H2O Zone. Here are a couple of pictures ...
Here is a link to several more photos of the H2O Zone ... http://www.cruise-addicts.com/photogallery/v/Freedom+OTS/?g2_page=3
4) As a first time cruiser, I would strongly suggest that you stick to the ship sponsored excursions. Until you know what you are doing, it is not a good idea to go off on your own. Going on a private excursion requires homework and understanding the risks you are taking. If you go on a ship sponsored excursion, the only real risk you take is paying more for the excursion then you would if you knew what you were doing and did your homework.
5) I recommend having the tips charged to your on board account (Sail & Sign card). Paying your tips in advance is like tipping the waiter or the waitress before you even get to the restaurant.
6) One of the least expensive times to cruise is between Thanksgiving and Christmas. The weeks of Thanksgiving and Christmas are very expensive. However, the three weeks in between those two holidays are some of the most inexpensive. Also, if you are in the Caribbean, September is a prime hurricane month, while December is outside of hurricane season, which runs June 1 to November 30 (however, this has not been communicated to mother nature, so sometimes a hurricane appears before or after it should). Weather in the Caribbean is fairly consistent, with the summers being about 10 degrees warmer than the winters.
