To address the working out too young thing: I lifted weights (curls, pushups, benches etc.) when I was 5-7 years old. I did all kinds of lifting when I was 11 on, including shoulder presses, benches, all kinds of stuff. I'm 6'2" now, which is 4 inches taller than my dad and 12 inches taller than my mom.
Maybe it helped that I didn't do heavy squats or deadlifts? I think that as long as you stay with relatively light weights you don't have to worry. (richard Sandrak looks pretty short for his age at this point- the really buff 10 year old kid on Ripley's)
Jacob