You will all have a fantastic time. Here are my tips...The parks will be pretty busy since that is just after Easter and spring breaks are happening. Start early so that the crowds are less, and spend afternoons napping and swimming(the kids will love All Star!). Then after everyone is rested head back out. Map out what attractions you would for sure like to see, and fastpass if at all possible. That way you can enjoy something else while waiting for your fastpass time to roll around. Take water bottles with you for you and and the kids, use a stroller for the kids so they don't get too tired of walking, and don't get stressed out! There is so much to see that you probably won't get to everything during the time that you are there, and that is okay! It will give you a reason to go back some other time. I recommend Chef Mickey's for a meal because they have more charactors than anyplace else, the food is good, the your kids will love it! Hope this helps, read everything that you can, and have a great trip!
Laura