There are several resorts that can accommodate your family. Depend on what you want and what price range. I would contact Ecologic divers
www.ecologicdivers.com as they can book you into the specific type of resort you want, they work with most.
Most of the resorts are condo style so they will have a kitchen as well as a living area.
Like jdub said Banana's is south, very nice with a pool, easy to get to via bike or golf cart. Xanadu, is a little closer, they have bikes they give you to use while you stay with them also they have free kayaks to use. Xanadu is a little more expensive than Banana's others closer too town. The Palm, Paradise Villas, it truly is better to work with a local shop as they can give you information on all the resorts.
As for dive operations, Amigos is by far the largest on the island there for they tend to have the most people on their boats. Protech, good shop, takes out smaller groups
speak with Peter the owner about packages. Ecologic Divers another good dive center located next to Amigos. Ecologic is a newer shop with new gear, started this year by a few instructors and divemaster. Contact Suyupa for resort,diving and trip info at ED. If you choose to do the blue hole the best is Amigos as they have the largest boat for the 2 1/2 hour ride. for the local reef diving you cannot go wrong with any of the above dive operations.