My husband, I and three of our kids aged 6-17 cruised on the Disney Dream in July '13. We enjoyed both the on board entertainment, the snorkeling and Atlantis (extra cost), the delicious meals, the dining experience every night and the two stops at Nissau, Bahamas and Castaway Cay ( Disney's private island).
The fourth of July fireworks was an experience to remember. Our kids' stateroom was next to ours so we had family nights too. We ordered food twice to the room and it's 24-hour free service. I'm not sure how our host (housekeeper) did it, but he literally came in to clean and arrange our room each time we stepped out! The two servers at the three separate restaurants made our day every night!
My hubby and I enjoyed a relaxing time at the spa; it was very well equipped and professional. I will recommend this cruise to any family - even though you don't have kids or they are grown up as there are so many grown-up activities on board.
The downsides to the cruise are the high cost and the pressure to choose one or two staff who made your stay memorable ( at least 4-5 people will treat you so well, so it's hard to narrow it to the best).