Good stuff soccerchamp.
One little addition. When figuring Batting average as Hits/At Bats
you forgot to include that At Bats do no not include sacrifice bunts or sacrifice flies.
BA = Hits / PA - BB - HBP - SacFly - SacBunt
Here's a good one:
One out. Runner on first. Batter hits the ball to the second baseman. Second baseman throws to the shortstop to force the runner at second and the shortstop throws to first to try to complete the double play. Batter hustles as fast as he can to first and just beats the throw, saving the double play. Should count toward OnBasePercentage, no?
No. That is a 'fielders choice' (FC 4-6 if you are scoring at home; and if you are scoring at home what are you doing watching baseball

) and does not count as a hit or towards OBP.
BTW, the infield fly rule has been in effect for over 100 years. It was obvious from the very beginning this rule had to be there to make the game fair.