We looked closely at both, just recently. Both seem very nice.
Windsor Palms is older, more house quality variation, fewere on-site amenities. It's also less expensive.
Windsor Hills has a water slide and many nice amenities, particularly for children. Water slides, playgrounds, small movie theater, games room. But it's newer and pricier. Some houses are only 1-2 years old.
I was at war with myself over choosing. VRBO has many places in each (as do several other rental sites--I looked at many!). We ended up going with a Windsor Hills home that's owned by a family with several homes. My thoughts were, kids will enjoy all the on-site amenities and the family has an excellent track record for renting. (BTW, I went with Romancing the Mouse--they've been great so far, but I havne't actually stayed there yet. We're renting a 4BR house for ~$1200 for a week.) It really depends on if you think you'll use the other on-site stuff. If not, go with Windsor Palms and save a few bucks. Personally, I know my kids will, and I can be super cheap, and sometimes DH has to remind me that it's not JUST about saving money, KWIM?