The fan... 1) You don't go after a live ball that's still on the field. 2) This is especially true if your team hit it. 3) It's even more critical if your interference with the ball would rob your team of a triple by turning the hit into a ground-rule double. 4) Even if you ignore all of the above, your grab for the live ball shouldn't resemble a punch. I don't recall any windmill motions in my fielding of Little League ground balls back in the day.
1) Fans are not all psycho types who want to smack you at every opportunity. Get over yourself. 2) Quit claiming that thoughts of what happened to Ron Artest were going through your head, thus allowing you to maintain your control. You didn't maintain control. You lost it.
That is all.