Hi B.,
I also think the disney cruise experience would be great.
I can't speak to it, but can speak to my cruising experience (close to 10 cruises now) with my now 7 year old daughter.
We're older parents and at this time of our life we want to do more travelling. We always bring our daughter with, and cruises have worked great. We get to have special time with her, and we get all the adult time we want as well when she participates in the kids programing.
I have been on Princess, Norwegian and Celebrity and Costa. They all had lots to offer for kids. I think I'd have to say Norwegian has the best kids programs I've seen so far....but just about all cruise lines have well developed kids programs that run a good part of the day and night (not all offer programming to 2 year olds, so if you don't do Disney, you'd want to check on this).
I've heard Carnival and Royal Carribean have programs that rival Disneys.
The best parts of the cruise experience for my very active daughter are swimming in the pools, getting room service, playing in the kids programs, going to beaches, listening to the live music that they have all over the ship, helping me with Bingo, watching outdoor movies (both Princess and Carnival offer this on some of their ships)and just the excitement of being on the ocean.
She's been cruising since she was 14 months, and has enjoyed all the trips we've been on.
Hope this helps.