We just went for the first time in June. We had the time of our lives. Want to plan a Christmas trip. From your experience, how bad is thanksgiving week?
I went for 3 days last Thanksgiving (Tue, Wed, Thu). It was fun, but the crowds were almost oppressive. We were able to book dining and most fast passes we wanted (we stayed in a cabin at Fort Wilderness). Cabin was awesome as well. The lines were outrag out without a fast pass though. Let me know if you have any specific questions.
We went for the first time during the week between Christmas and New Years. Honestly, I noticed that the crowds were intense, but we had such a great touring plan that the crowds really didn't impact us that much. We never waited more than 15 for our ADRs and the wait for Quick Service meals wasn't bad at all. We never had any issues with transportation either. We are heading back for our second trip during Thanksgiving week this year and I'm hoping for slightly lighter crowds than what we saw before. I think one of the most difficult things for me from a planning perspective was the change in hours and addition of extra magic hours that came so late. I had a few early morning ADRs that I switched due to a change in park hours. You will do great as long as you have a good touring plan and realistic expectations.