Removed IE8 from Turn Windows Features on or off, rebooted, tried installing IE9 cleanly
So at the moment, if you click on the IE icon, no web browser comes up at all?
I ask because you said that you turned IE8 off in "Turn Windows Features On or Off" and that even though IE9 didn't finish installing, it now (IE9) shows up in the listing. I just checked for IE9 under "View installed updates", but didn't see it listed, even though it is indeed the version that is installed on this computer. And yes, my original Windows 7 install came with IE8 as well.