I would not skip Epcot. My brother (12 now) and I loved it when we were younger. He loved Spaceship Earth, Innovations, the soda tasting location (forget the official name), the Land, Nemo and Friends, the Ellen ride, and the countries. They try to make the countries fun for little ones too. They have a large- scale train display in Germany, the ride in Norway and Mexico is fun, they now have the Kim Possible attraction throughout the World Showcase, and of course they have Duffy the Bear "masks". Spaceship Earth was recently updated and now part of it is interactive so I think your six year old would really like it. I would not worry about wasting a day because there are way too many things to do there.