Holding back tears, Oprah Winfrey told her studio audience Friday that she would end her show in 2011 after a quarter-century on the air, saying prayer and careful thought led her to her decision.Winfrey told the audience that she loved "The Oprah Winfrey Show," that it had been her life and that she knew when it was time to say goodbye. "Twenty-five years feels right in my bones and feels right in my spirit," she said.