Sorry for the late response on this. I have spent the past couple of Thanksgiving weeks in Breckenridge. Winter of 2015/2016 was fantastic at Thanksgiving, quite a bit of Peak 8 and 9 open. 2016/2017 Thanksgiving weekend had very little in terms of runs open and it was a bit crowded on the runs that they did have open. This past year, the snow was mostly man-made, but they had done a good job of it and there was some good ski-able terrain.
I recommend reservations weeks/months in advance at most of the nicer restaurants serving an official Thanksgiving Dinner. Room rates are reasonable during Thanksgiving and early-to-mid December and their are not much in terms of crowds.
If there is some snow, there are snowmobiling and dog sledding places in Breck and the town of Frisco has a snow park that includes tubing.
I'm a bit biased because Breck is one of my favorite mountain towns.