Yeah the only reason he seemed so young is because he turned his own body into that if a puppet, which cause it to stop aging. Only his Heart remained relatively intact, becoming his weak point and the key to defeating him.
No. He got DEFEATED by Naruto, and while he were lying on the floor, unable to do anything anymore after being destroyed by Naruto's Rasenshuriken, Kakashi finished him off with Raikiri.
