Traditionally, after the Thanksgiving weekend, and before the first weekend of the two week Christmas-New Years holiday, is a quiet time at Disneyland. Now the weekends might be busy with the Candlelight processional the first weekend and the other the last weekend the local AP's have to see the holiday decorations. Other than that, it should be a nice time.
Jiminy Cricket Fan
Yeah, we have always gone to the Resort for the week starting on the sunday after Thanksgiving. Now we enjoy out T-Day at the DL Hotel for the Buffet, but avoid the Park on the friday and saturday, and stay through the following thursday.
Sunday lightens up as the day goes on and from monday through thursday you should be very pleased with the (lack of) crowds.
It's the best week of the year to enjoy the Parks.
The closer it gets to Christmas, the busier the Park gets. Plus some days the Park will close at 6pm for private parties.