My wife talked me into buying a 7-day cruise from New Orleans to Jamaica/Grand Cayman/Cozumel. We went there with our two kids, aged 5 and 6. This was my second cruise (the previous one was a shorter, 3-day in Southern California) and quite possibly the last, at least until I can afford to pay more for a more decent experience (with tips and onboard spending, but not including the cost of getting to/from New Orleans, this trip came out to about $3000 for the four of us).
The good:
Generally, good food. Decent variety of items at the buffet for breakfast and lunch. I liked the salad bar. Even with all those unlimited desserts, I managed not to gain too much weight because of it. Dinners were delicious. Extra point for Indian vegetarian entrees. There was a sushi bar (which I, unfortunately, did not get a chance to try because it was closed or selling teddy bears most of the time.)