I completely agree with your decision not to tell your kids about the OW. However, this isn't because I've spoken to psychologists or read about it in a book. It's because as I've told you already, when I was 10 my dad was having an affair and it broke my parents marriage wide open. As soon as the M was over, my dad introduced us to OW. That was one of the worst experiences of my childhood. To this day I still feel dislike towards the woman who did that to my family. The break up I could handle but was too young to understand the affair.
Your kids will learn about your H's affair in due course but only when they're ready to understand it. IMO they will be ready to know when they understand enough to ask the question themselves. Right now you're completely on the money in your opinion that telling them right away will just breed hatred. One thing at a time PM. That's enough for any child.
Kev X
Me: 32, Wife: 22 Son: 2 Married: 2 years Separated: January 5th 2009
Sometimes you have to become lost before you can find yourself.