I'm not sure what your budget is, but I would go with Coronado Springs or Old Key West.
CS is primarily a convention hotel & I rarely see kids there. It's an all around great place, particularly for the moderate price. The american southwest/mexican theme is more adult-oriented, so don't expect to see any characters running around. Bus service here is good also.
Old Key West, while expensive, is a dream. They're nearly condos with kitchens, large bathrooms, etc. Go with the one-bedroom though, not the studios. The studios are basically regular hotel rooms at ridiculously high-prices. The resort is extremely quiet, peaceful and private. A nice perk here is the nightly boat ride to Downtown Disney.
I agree with one of the earlier posters about avoiding the value resorts at all costs (All Stars, Pop Century, etc.). They're noisy and swarming with kids. Almost as bad are the moderates Port Orleans & Carribean Beach.
I also like Animal Kingdom Lodge, mainly for the great atmosphere. It does has some kids around, but not too bad.