After watching “The Shop Around the Corner,” consider tracking down these time-tested treasures to bring a bit of extra romance and laughter to your holidays. “It Happened on Fifth Avenue” Rarely seen these days, this charmer of a Christmas comedy involves a loosely knit band of homeless folks, including several WWII vets, all taking shelter at Christmas in a boarded-up mansion, unaware that some of the them are actually the house’s wealthy owners in disguise.