veris, me think your son wont be able to go to most of the rides. We went just around 2 years ago and my son was nearly 6 at that time, he is dare devil and cant go to some of the rides because of height restriction. But it is still will be a good fun to see all disney character roaming around. They have 2 parks next to each other, so it would be better if you stay over night and visit 1 park a day and explore everything.

The good time around that time you dont have to queue but make sure you check their closing time because in the winter most places close early.