Hi Lisa,
To have a separate sleeping area, you will need to have either a suite, a deluxe villa, or connecting rooms at any of the resorts. Suites are available the
Deluxe Resorts &
Coronado Springs, a moderate resort. In addition, family suites are available at the following value resorts: the
All-Star Music Resort & the
Art of Animation (opening the summer of 2012).
The
Deluxe Villas are part of the Disney Vacation Club, but they are open to all guests. These will also include small kitchens & a washer/dryer (not in the studios).
The
Cabins Ft. Wilderness are another option since they also have a separate sleeping area.
When our children were toddlers, we loved staying at a Magic Kingdom resort (Contemporary, Grand Floridian, Polynesian, or Bay Lake Tower) because of the easy access to the park by monorail, walking, or boat, depending on which resort. It made it so easy to come and go to the park we spent the most time at. While staying at the Animal Kingdom Lodge near the Animal Kingdom is truly magical, it does have longer bus rides to all the parks.
I'd explore the above links & see which meets your budget, needs, & tastes best. If you need more information, please let us know!