Palin says presidency "not on my radar screen"

"There's the perky one, with the microphone, with the questions," Palin said disparagingly.

"You're pretty perky, too," Winfrey remarked.

Asked about Johnston, Palin said she did not want to respond to his criticisms, which have included comments that she is a poor parent and not getting along with husband Todd.

"We don't want to mess up the gig he's doing: aspiring porn," Palin cracked, referring to his appearance in Playgirl, an online magazine that features nude men. "I also saw I didn't go to hockey games. There are so many untruths."

Levi is still welcome to come to dinner next week for the U.S. Thanksgiving holiday with the Palins, she added. "He's family."