That's kind of the issue I'm having. On Windows 7, I can can see IE11 as an update. When I uninstall it and restart, I have IE10, and I can repeat that until I'm all the way back to IE8. Or, I can go to "Turn Windows Features on and Off", uncheck IE11, and have the previous version of IE show up when I restart.
All the advice I can find online says I should be able to do the same thing in XP to go back from IE8 to 7 to 6.
I've looked on the three copies of XP that I've installed, and IE8 doesn't show up as an update. If I uncheck "Internet Explorer" in "Add/Remove Windows Components", then IE doesnt show up at all when I restart. I was starting to think that some builds of XP released after some point might not let you roll back earlier than IE8?