No, as I said in my heading I have uninstalled IE8 so currently have no IE installed on my computer at all, however, when I try to install an earlier version it says I already have a later version installed which i don't.
I need to know how to remove all trace of IE from my computer so I can start with a fresh, clean installation. I don't know whether SP3 was installed before or after IE8; it was ages ago.
You definitely don't need to or want to remove all traces of Internet Explorer.
Go to Start> Settings> Control Panel> Add or remove programs> Add/remove Windows components> put checkmarks next to Internet Explorer and Outlook Express. OK your way out.
No, as I said in my heading I have uninstalled IE8 so currently have no IE installed on my computer at all, however, when I try to install an earlier version it says I already have a later version installed which i don't
Yes, you do. What you did is an illusion. It does not uninstall all of IE, it just hides its shortcuts. Later versions of Windows go further and can actually hide its main executable, iexplore.exe but even that still leaves all of the OS browsing support
left at the level that you would call your IE if you still could see it. Use msinfo32.exe to see this. In all OS you can use its Loaded Modules list sorted by Version descending and then see the browser related ones grouped near the top with the version
of IE that your OS supports. However, with XP you could also use its specific IE Summary report to check on your IE status. Or more directly Run... (e.g. press Win-R and enter:)
msinfo32.exe /category IESummary
And provided you haven't also deleted your iexplore.exe you could also Run...
iexplore.exe -nohome -extoff
and then use the normal Help, About display to see your IE version in an actual running instance.