I agree with the previous posting that recommends taking the buses as much as possible.
Also OKW is a great place to stay!! You will find that it is HUGE, a 2 bedroom villa is about 1300sq ft (my HOUSE is 1600 sq ft) and of course a full size kitchen.
The bus stops are not far away from the rooms and you don't share your bus with other resorts (like Port Orelans riverside and PO french quarter) PLUS since it is a Disney Vacation Club (DVC) resort, your drop off and pick up locations at the various parks is very close to the enterence/exit.
My kids (2 yo girl and 3 yo boy) just LOVED taking the buses everywhere. And don't forget the strollers!!! You really do not want to rent them at the parks. I guess it depends on what you have now. We had a rather decent double stroller that allowed us to carry those items that always seem light at first but become amazonly heavy by the end of the day.
Hope that helps!!