I have been to Disney 3 times in mid-to-late October, and the longest line I have stood on would be about 20 minutes.
We have ridden Space Mountain, TOT and R&R coaster over and over again with no wait.
I am going in January, but I will be going back again this year the third week of October.
I have never been there the week after Thanksgiving, but I guess even if the crowds were equal or a little larger, it would be worth it because the Christmas decorations would be up. BUT, that could be one of the reasons more people go at that time than October.