I added the blocked Heur.Agent/Gen-FakeIE to the allow list in SAS - started IE8 and disabled a few of the add-ons in IE - like Google SideBar, Google updater, and a few others that seemed unnecessary. Sorry I can't be more specific, as I wasn't paying real close attention as I was disabling them.
Also, I went to the Advanced tab in IE's Internet Options and clicked "Restore Advanced Settings" and "Reset.." to assure everything is set at default.
Closed IE8, removed the Heur.Agent/Gen-FakeIE from the Allowed/Trusted list in SAS preferences. Assured realtime protection is still enabled in SAS.
Now IE8 opens up fine without any warning or blocking of Heur.Agent/Gen-FakeIE.
Hopefully this will help the others having this issue.
My guess is it's an add-on for IE8 that is either infected or a False Positive.
Just wish I paid closer attention to which ones I disabled. (DOH!)