With kids that age I would concentrate just on one area. For example, you could take them to the 3 monorail resorts. You could start with breakfast at Chef Mickeys, walk around the CR after eating, then hop the monorail to the Poly, hit some of the shops there, take the kids down to the beach, show them the Volcano, the waterfall, etc, then hop the monorail to the GF, maybe rent a pontoon boat and take the kids out on the water, have lunch at the GF cafe, etc. That would be a fun day.
Another idea is you could hit the Boardwalk area. Start with a character breakfast at the BC, walk over to the YC and check it out, then head to the BWI, there are shops and carnival type games and stuff there they would like. There are a couple of different ice cream places too, and boat rental at YC. Another fun day.
DTD is also a fun day away from the parks. Kids will love
Legoland, World of Disney, Once Upon a Toy, magic shop, there are tons of places to eat, movie theater, etc.
Sometimes I think our days away from the parks are my favorite.
