Random Iron Man thought...

Just how old was Howard Stark when he had Tony?

Think about it...  in 1942 we see Howard at his youngest. The actor who portrays him is in his 30's. He acts like a guy in that age group. Lets set him at 30.

In 2008 we first meet Tony Stark. Now, by that time he was being played by a man in his 40's, but he was acting more like a man in his 30's. Let's assume, that was just Tony's youthful spirit, and say Tony was just 40.

Now, doing a little math, that would put Tony's date of birth around 1968.

That means Howard Stark was in his late 50's when he had Tony.

Not unheard of.. but still, a late father.

As a side note: The actor who played Howard Stark in Iron Man 2 was a man in his 40's. Assuming he filmed it just before or right at Tony's birth, that would work out fine with the age of the actors.

A side note to that note: that Actor, John Slattery, would go on to play another man in his 40's in a story set in the 60's.  Hmm... Iron Mad Men. That would explain all Tony's Sexism, and the booze.