Varsity Baseball: Homerun with Runner on First - Who's Out?

Question
Varsity baseball- With a runner on first and one out, the batter hits a ball over the fence for an apparent two run homer. Unfortunately, the runner on first stays near the first and is passed by the batter-runner. Obviously someone must be out? Who is out and what base is the remaining runner placed on? Thanks

Answer
Angel,
I believe that the hitter is out as soon as he passes the runner ahead of him.  The passed runner can score because of the ball being hit over the fence.  If there was two outs then no runs score and the inning is over.  I would double check this ruling with an expert umpire.

Thank You,
John Priest