On Saturday, the Beverly Hills Presbyterian Church had all the ingredients necessary for a successful westside Yuletide celebration: majestic choirs, a rousing performance of Handel's Messiah, and a celebrity supermodel to read the Christmas Story. Happily, not even the last-minute cancellation of planned "special guest" Hunky Santa could damper the spirit of the season; not a soul complained when it was announced to the congregation that the musclebound St. Nick wouldn't be able to attend due to a shift at the Beverly Center that ran too long.