This is one of my all-time favorite episodes in all of TV, not just from Happy Days...and probably my favorite Christmas episode to be watched. There is something very special about this episode that's hard to pin down. Part of it is that Chuck's there, so we have a rare occassion with the entire family. It's fitting that Fonzie stays for Christmas, as he becomes like a member of the family as the series moves on. Part of it is because the series was still young and finding itself, so it relies on the true spirit of Christmas. These and other elements make this a very classis Christmas episode that is a must-see during the season.
It's too bad Fonzie's story was made up, though. I would have love to seen that Christmas Eve setting up in that big house in Waukesha!