I think you're saying if he was born to at least one parent who was a U.S. citizen he would be considered natural born. I also believe that to be the case. But there seems to be disagreement about that.
Actually, I'm in the camp of two citizen parents to confer natural born status. See my tag. I believe these two things:
1. When the Preamble speaks of "We the People... secure... the Blessings of Liberty to ourselves and our Posterity..." it means that both parents (the parents of the Posterity - their children -) are of The People (citizens). Limiting the President to natural born citizens was how they meant to secure liberty; they wanted to ensure that the President was the posterity of two citizen parents, that is, of We the People, not just "me" the People.
2. Thomas Paine wrote in The Rights Of Man (1789) that the United States was the only country that required its President to not be "a foreigner" or "half a foreigner," meaning both parents had to be citizens. See Chapter 4.
If Obama's birth narrative is true, then he fails the two citizen parent test for natural born status, in my opinion. If we accept the single parent citizen test, then he fails if he were born outside the United States because his mother was not old enough to confer citizenship status at the time, making him British by birth.
-PJ
I don’t know the answer to the age issue and the five years because Zeros mother was only 18, that eludes me, but this State/Fed doc gives 69 pages of ‘natural born citizen’ info at this site.
http://www.state.gov/documents/organization/86757.pdf