I have been to the special Christmas Hoop Dee Doo show, I went to it a couple years ago. On Christmas (I think it was Christmas..either Christmas or the night before Christmas). If I remember correctly, it was mostly the same, but they had winter additions to their outfits (wraps, hats, coats, muffs, etc), and there were some Christmas-y songs. It's all kind of fuzzy because it was the late showing, and I was really tired. The food was the same as usual from what I remember as well.
I have no idea if it's always during the Christmas season, or if it's only on actual Christmas though.