For longtime fans of Saturday Night Live, nothing says "Christmas" like clay, and the hapless hero of Walter Williams's sadistic skits brings it all back in this half-hour 1996 special. Those who can't stand watching the torture of static, crudely sculpted Play-Doh people might not see the humor as Mr. Bill's whole family is subjected to a wide array of holiday abuse--from the festive blendering of the egg dog to the explosive arrival of the sinister Santa Sluggo. Things are livened up by spiritual guest Father Guido Sarducci and his quest to find a real Christmas in sunny L.A., home of many former SNL actors and writers. Mr. Bill also takes a technological leap forward as a reluctant Scrooge in a computer-animated version of Dickens's A Christmas Carol. Humorous ads for some very simple toys also add to the fun and festivity. And when you think it's all over, keep watching--the real gem of the package is slipped in after the credits. It's an example of the real thing, a Mr.