Oprah‘s former daytime rival Phil Donahue empathizes with her decision to hang up her microphone in two years. “She’s a remarkable story,” the talk show legend told The Post’s Kirsten Fleming at Monday’s unveiling of Saks’ Christmas windows. Donahue, looking dapper in a Canali overcoat, mused, “But you’re on air every day. Eventually you think, ‘do people really want to hear me talk anymore?’ ” And don’t expect him to jump into the coffee-klatch game again. “We were on for 29 years. I’ve already seen that world,” he added. Also on hand were adorable members of the choir from Bronx PS 22 who wowed fashionistas like Fern Mallis and Nanette Lepore with their rendition of Jay-Z‘s “Run This Town.”