It really all depends on your son. Some kids can sleep easily in thier strollers while others don't. We first took our son when he was almost 2.
First, it's good you've been to WDW many times before. You know the ins and outs and also the quality of the rides, attractions, shows so you can decide which will be best for your child.
I had been many times before I first took my son and when we went it was totally for him. There were many favorite rides and attractions we didn't do because they weren't right for him - but we had so much fun doing what he enjoyed with him.
A few suggestions re sleep and schedule:
Make sure you have a comfortable stroller that reclines and has a sun shade so that it will be more condusive for your son to nap if he neds to while in the parks.
Afternoon break time / naps back at the resort are good especially if you plan to do a nightime parade or fireworks.
The child care centers are good for changing diapers or cooling off. I've only been to the one at MK and it has a room with a TV playing Disney movies that kids can watch. As far as napping - there are no beds and such -you leave your stroller outside - not enough room for all those strolllers inside. So if your child was to nap it would have to be in your arms (if you can get an empty chair).
Riding the monorail around the resort loop. Hanging out at one of the resort lobbies on the monorail or by the EPCOT hotels are other good places to relax and let your child nap in the stroller.
Try to keep your meal schedule to what your child is used to. Eating too late or too much time between meals can lead to a cranky toddler. We planned all out ADRS arround the time DS usually ate at home. Also make sure to bring favorite snacks and food from home.
Your child will let you know what they need. You can only prepare yourself so much because you won't really know how your child will react to the changes in schedule until you get there. Again, the fact that you have been there before is helpful in that you won't mind if you miss any attractions or rides you've already seen if you need to make adjustments for your son. Being felxible is the most important advice I think...just follow your childs lead and you'll be fine.
Have a great time!
We also know we're going to visit Disney often, so we don't feel the need to experience everything.
I'm sure on the days that we plan to be out later than usual we will certainly head back to the resort and let him have a good nap. Who knows....maybe the hubby and I will need it too!
