Wow, 4 dd's... I'm impressed!!

How old are yours? I have 3 ds's, ages 1, almost 6 and 8, and we've stayed in a studio at BCV before. It was fine because the older 2 slept together in the double sleeper sofa, dh and I slept in the queen bed and the baby slept in the pack n' play. We're hoping to do the same thing during our next trip. I would say, though, that once our baby gets too big for the pack n' play, we'll probably opt for either 2 studios or a 2-bedroom. The 2 studios would be much less money than the 2-bedroom, but they aren't adjoining -- I'm not sure if Disney will guarantee that they're next to each other... The advantages of the 2-bedroom are that you have the full kitchen, great jacuzzi tub and the washer/dryer, all of which would be nice to have. The 2-bedrooms officially sleep 8 (there's 1 king bed in the master bedroom, 1 pullout sofa in the livingroom, 1 queen bed and 1 pullout sofa in the other room and 2 bathrooms, one of which that has a shower and jacuzzi tub and the other of which just has a standard bathtub with a shower).
A few other ideas you might consider are as follows:
1. A deluxe room at WL (this would sleep 6)
2. A Ft. Wilderness cabin (they sleep 6)
3. 2 rooms at a value or moderate resort (which I think would be guaranteed to be next to each other)
That's about all I can think of at the moment... If you have any other questions, feel free to ask!
Happy planning,
Sarah