We dined at Disney last Thanksgiving and had dinner at Grand Floridian Cafe. My wife and I were very disappointed. Our waitress had a very large table that occupied her time and all of our food was brought out together. We had an appetizer, salads, and turkey with trimmings and it all came out in 5 minutes time. I do not rec. this. The next night we ate at the Mexican Rest. and they still had their thanksgiving menu. Why would anyone order turkey there??? Well that was me! It came with some green sauce on it and was terrible.
Every other meal we had that weekend were great! We ate at Ohans, Prime Time Cafe, Chrystal Palace, and I forget where else.
If we were to do Thanksgiving there again I would probably go for something like Boatwright's at Port Orleans or maybe the Land in Epcot. I don't know if they offered anything special but the experience for me has always been good there. What about the England Pub in EPCOT? Liberty Tree Tavern is the place I'd consider as well.
Hope you find this remotely helpful!
Doug