Marriott Orlando World Center has a lovely, large main pool area, with a nice slide for the kids, waterfalls, a couple of hot tubs, poolside bar/grill service, two other quieter pool areas, small indoor pool, video game room, glass elevators, and golf onsite. If you are looking for villa accommodations (2-3 bedrooms, 2 baths, full kitchen, washer/dryer, king MBR w/jacuzzi), there are three timeshare resorts on the MOWC property as well.
Each of those (Royal Palms, Sabal Palms & Imperial Palms) has its own quiet pool area and a free (+tip) shuttle van will bring guests to/from MOWC if you don't care to walk. Very nice. Guests are granted access to MOWC's facilities, restaurants & shops. MOWC is very near Disney, just off the same I-4 exits.
Sunterra Cypress Point resort (another timeshare) is less than a mile from Downtown Disney, with a modest volcano slide (great for young school-aged kids). They have studios as well as 1-3 BR villas.
Isle of Bali (now called Ron Jon) is another timeshare resort, in Kissimmee. They seem to get generally good reviews but some mixed. Their big draw is a mini-water park, Liki Tiki Lagoon, designed for elementary school kids and younger (several slides, water sidewalks & water toys).
Of all of these, I'd prefer MOWC's villas. Hope that helps.