No job, no kids, no worries. Just you, your family and fun. Would you do it if you had the chance?
Personally I wouldn't. Yes not having to worry about work is phenomenal but in my opinion the freedom of choice that I have as an adult far outweighs anything from my childhood. Not to mention NO SCHOOL. K-12 was absolute cancer growing up, yes work sucks ass but high school sucked MASSIVE ass, what a shithole of a prison highschool was to me.
So what about you? Would you return to childhood or stay the adult you are now?
Edit: No you're not able to keep your current knowledge, your knowledge retreats back to the year you decide to start.