If you could go back in time and give some advice to your younger self, what would it be? What age would you go back to in order to deliver this advice? Do you think your younger self would listen to you and heed the advice?
I would never do it. Even a very small change in past events can have huge consequences. If I went back at any time earlier than 1990, I might never have ended up marrying Kathy (and in fact any change up until the wedding could do that). Sure, there's things I regret doing and would like to change, but the likelihood is that I'd cause something -- maybe a LOT of somethings -- to change in a way I didn't like.