Windsor Hills is a residential development---it's like staying in your uncle's very nice vacation home. Tons of privacy, particularly if you have a home booked with a private pool. There are some nice neighborhood amenities (pool, etc.), but the focus is on a quiet, private getaway.
Bonnet Creek is a timeshare resort. More active, not as private, but more resort amenities.]
Which is "better" comes down to what sort of vibe you are looking for. We like the more "resort-y" atmosphere at Bonnet Creek, but YMMV.