Dena,
You have come to the right place to clear up Walt Disney World confusion!
First off, all of the Disney resorts are great for families. But with kids your ages, I would recommend the following, by class;
Deluxe:
Grand Floridian or
Polynesian
Moderate:
Port Orleans Riverside
Value: Pop Century or Art of Animation
If budget is not an issue, the two Deluxe resorts are especially nice for you, as they are on the monorail and will get you to the Magic Kingdom quickly. That is sure to be your most frequent destination!
As for the crowds both before and after Thanksgiving, I would say that the week after is a bit less crowded than before, but not by a lot. Either one would be a VERY GOOD time to visit!
Feel free to write me follow-up questions from my bio page!
Have a magical vacation!