Was the version of the Thanksgiving Theme I posted in the link above the original version? It sounds like it to me. I have the 2012 cd and thought that the versions of both the Halloween special and the Thanksgiving special were re-records.
Not sure it is the same recording, but certainly the same arrangement. It is fairly time consuming to figure out which versions are different recordings.
The Thanksgiving music, including "Little Birdie," also appear on both "Peanuts Holiday Hits" and "Peanuts Portraits." All these years, I had no idea that was Guaraldi singing "Little Birdie!"
Back to the original question, I am less interested in which are the same recordings than I am in arrangements that have not shown up on CD, hence the question about "O Tannenbaum."