A solidly-built leading man of TV series and feature character player with much stage experience and a powerful voice and presence, Darren McGavin worked seemingly non-stop since his professional debut in 1945, becoming best known for two very disparate roles: the supernatural-entangled crime reporter Kolchak in the TV series "The Night Stalker," and the crusty, wildly cursing family patriarch of the nostalgic holiday perennial "A Christmas Story" (1983). Born in Spokane, Wash., McGavin was sketchy in interviews about his childhood, explaining that he was a constant runaway at 10 and 11, and