I don't have much to add to what the others have said, just that you sounded so skepitcal in your post I wanted to reassure you.
Though situated on the FW grounds, the cabins are just as well equiped as any villa (except for the washer/dryer). It is nothing like camping. Mousekeeping comes every day. They will even do your dishes (in the dishwasher). The cabins are modified trailer homes. There is central air conditioning, cable T.V., a phone. One nice thing about FW cabins is that they are stand alone units, so you do not have the noise from the people next door or overhead.
The only things I can think of that you might want to bring are:
- food, including any condiments/seasoning you use and coffee (they supplied us with 1 day's worth of coffee. It's a small pot)
- coals and matches, etc if you are sure you want to bbq
- laundry soap (in a ziploc) if you will be doing laundry and a bag to carry your dirty and clean laundry to/from the laundromat
You are right, it is good value for on-site. I think you will enjoy yourselves. We did not take advantage of everything that there was to offer at FW, but we still had fun. The pools are not themed, but they are well equiped with changing rooms and bathrooms. They had a big bin of life jackets for kids who don't swim. The pool we went to had the laundromat right next to it so you could do your laundry while you swam.