I would recommend it, I had heard from many experienced travel goers that Royal Caribbean is the better cruise line to take. I am told Carnival is a very much a party cruise line with lesser quality food. If you have kids there is much for them to do. There are a lot of adult activities as well. Disney is very expensive. My best advice is check where you will be leaving from. Many ships don't depart from certain areas.
I actually would probably start with Carnival. Carnival is like "the fun ship" where it's less quality but cheaper and caters to young people. You should build up to RC, if you start with them, everything else will disappoint IMO
YEs it is way better than Carnival. It is a little more expensive but well worth every penny. The bigger the boat the better. The Oasis and Allure boats are amazing! They are the biggest cruise ships out there and cost a little more but you will not be disappointed. I won't go back to a smaller boat.