After weighing our options of reviews verses price and on board options we decided to go with Carnival- it was by far the cheapest for 5 people, had rooms for 5 people, and take 2 year olds at the kids camp- no other cruise lines starts at 2 (EVERYONE else starts at 3, they may offer paid babysitting but not inclusive kids camp) and with two two year old girls that was a HUGE deal.
We had heard a lot of things about Carnival being the "booz cruise" and being how any cruise line in the Caribbean is the "party" destination. But we had also heard that it isn't as bad as the rumors say and we hoped we made the best choice considering all our needs.
We choose a 5 day cruise (that way if the children didn't handle it well it was shorter), out of Galveston, TX (because we could drive there and stay in budget), with two stops Cozumel and Progresso, Mexico (so we could see Chichen Itza).
We loved out shore excursions, Chichen Itza was awesome and in Cozumel we did a private island called Passion Island. It was awesome. We were a little concerned about the "all you can drink" alcohol but there was only one person who was obviously drunk when the shore excursion was over. The awesome part of Passion Island was the kids section. They had activities, and a play area and children supervisors that were great with the kids. We didn't fully leave our children there (although we could have) we sat up next to the play area were we could watch them play. Our daughters discovered water color painting and did that for over an hour.