That's a toughie. They all have something to recommend them for families:
SSR has the zero entry pool and water play areas, as well as the spa and access to DTD to entertain the adults more.
BCV has the sandy beach kiddie pool as part of SAB, Cape May's character meals and access to Epcot and Boardwalk for all the adult entertainment.
VWL has the ferry access to Magic Kingdom, Whispering Canyon for family meals and a beach play area, plus there's the access to Fort Wilderness and all its family activities.
OKW has the larger dining room (the only real one on property IMHO) and bigger living room area. (With a dedicated two-bedroom, I think it would be a wash as far as number of beds.) And there's a pretty cool play area for kids by the main pool. You'd have ferry and bus access to everything else.
For kids your age, I'd probably stay as close to MK as possible. You might want to check-in to Cindy's Castle since you'll practically be living there.

Otherwise, it's up to what theme you fancy and what is available. Unless you own BCV and VWL, reservations may be hard to get. OKW & SSR will have the best availability for non-owners. I think in the "what's fun for adults", I'd probably pick BCV or SSR for their proximity to after-hours entertainment areas. (No knock at OKW but it's still about a mile to walk to DTD and/or requires a bus or ferry ride.)