I read a book with this as the main plot. I think it was called 'Replay'. A guy has a heart attack in his office when he's 45 and wakes up in his college dorm at 18 having to relive his life over again. It ends up happening several times so he has the opportunity to follow several different paths for his life. Quite interesting.
I wouldn't mind starting over from my teens again but only if I could know what I know now. Otherwise it wouldn't be worth it. I'd just be the same dumbass
