I've stayed at Banyan Bay and have also toured it a time or two. I think it's a terrific place. It has two-bedroom, two-bath condo-style units, and they're among the largest on the island, around 1,000 square feet. The units are very nicely and tastefully decorated. There's a full kitchen and living room area (beautiful hardwoods on the ceiling) and balconies/sitting areas with sea views. All the modcons -- A/C, cable TV, phones, etc.
It's about 1 1/4 miles from town, so it's handy to have a golf cart (Banyan Bay can arrange a rental, although you can rent your own). Or you can take a taxi, or walk along the beach.
There's a big pool and a pretty good stretch of beach. The times I've been there, there have been quite a few families.