I'm in your age range (well, just a tad older ), and any of those ships that you listed should do just fine.

I have only tried Princess and Royal Caribbean on my cruises to the Caribbean, and I prefer Royal Caribbean over Princess. I have heard very strong reviews from my peers that the food on the Disney Dream wasn't great (and that's an understatement, to say the least), so that's something to research more on if food is a major priority.

cruisecritic.com is probably your best bet. Lots of trip reviews there.