I think that your kids are big enough that you don't have to, necessarily, base your hotel on proximity to a park. That is a good idea with toddlers or preschoolers who may need to exit because they are tired or cranky, but by the time my kids were the ages of yours it usually isn't an issue.
Like was said, I would start with budget and length of stay and work from there. We are park people, so we, generally, don't feel the need to spend a lot on a hotel. For us it's to sleep, shower, and the occasional dip in the pool.
We are a big family. We have enjoyed the family suites at All Star Music (sleeps 6, kitchenette, and 2 bathrooms) We are considering a family Suite at Art of Animation for next year. For more budgety ideas you can also look into the cabins at Fort Wilderness, Caribbean Beach, or Port Orleans Riverside which are "moderate" resorts.
Renting DVC points can save you money on villas over rack rate, but it is still cheaper to get a regular hotel room.
There is something in each park that my kids like, so we generally hit all the parks. Although more expensive, we like the "park hopper" option because Hollywood Studios and Animal Kingdom as they are aren't full day parks for us, so after we see them we bounce to other parks to catch things we missed or want to do again.
