Seven days won't be enough time to see it all. You would still be able to visit the 2 Universal parks but you'll have to pick and choose what you do. You'll probably be missing the "bigger" rides due the ages of the children which will give you a chance to see more of the other stuff.
FWIW, seven days wouldn't be enough time for 2 adults "going commando" to see all there is at WDW (let alone adding US and IOA). See what you want and leave the rest of the stuff for the next trip.