The silvery strains of Frozen’s “Let It Go” may be a familiar sound in your household, but when Idina Menzel wraps her warm, stunning soprano around a cozy selection of Christmas nuggets, she sheds her icy Elsa image. The singer polishes some fireside classics with a retro shimmer and gets flashy and fashionable with Billy Porter on the punchy “I Got My Love to Keep Me Warm.”