A Granite or a 2wd Traxxas is going to be quite a bit for a 2 year old. My son went from 1/18 at 3 years old to 1/12 at 4 years then 1/10 a couple years after that. Why not get him one of the 1/16 Traxxas models?
If it were me, I would probably go with the 2wd Stampede if I were dead set on...