Depending on if you are looking for traditional fare, LTT is the only place that you are going to get that true Thanksgiving feeling. The place is just screaming Thanksgiving, very good food and service here.
Biergarten has a good buffet, and in past had turkey and the fixin' along with the German offerings... Be prepare to be so stuffed afterward... a nap will most likely be needed.
At this point you should more that likely be looking at just getting a ADR. I would look at Disney Springs...