OK...take a deep breath, make sure DH can get the vacation days & GO, GO, GO!!
We were on the Pride (a sister ship I believe) last November & we had a great time with our 4 year old & infant in tow!! Had it just been the two of us, it would have been an excellent cruise! Whereas
DCL's focus is on families & children, Carnival's is on Partying & nightlife. Even though we were in every night by 10pm (& THAT was a late night) we were never bothered by others partying. The food was right on par with DCL's. We didn't get to any of the shows, though I would imagine them to be QUITE different from DCL's.
The only one of those ports that we hit was Belize & everyone recommends doing an excursion through the ship. We did the Geoff's Cay (probably spelled that wrong) excursion & it was AWESOME. THE best excursion we have ever done. We took the baby & our 4 year old along. You are picked up on a boat directly from the ship & you speed away past all sorts of tiny islands & end up at the tiniest one of all!! Many stayed on the boat , including my husband & cruised around the island snorkeling (they were given bottled water free of charge). I went ashore with the two little ones & rested on the sand under some HUGE palm trees. There are NO facilities, no power, no running water. There were a few people selling t-shirts & whatnot, Beer & water, and also someone barbecueing some hotdogs & burgers. I believe we stayed for 2-3 hours & headed back to the boat. This island was TINY, not even as big as a football field!! But just gorgeous, if there weren't 5 or 6 other boatloads of people there I would say it was like an island out of a dream!!
Carnival has been at this cruising thing for a while & they really do have it mastered. Have a great time & MERRY CHRISTMAS!!