Microsoft recommends installing the older OS first, then Xp. I installed XPP then 98 and it would only boot to 98. I then reinstalled XPP but now can't get back into 98. It's ok because I really don't need both OSs- XPP is fine. So if you're going to do it, look at Microsoft's site about dual booting, they have a good basic introduction to dual booting and specific info on dual booting with each OS. <a href="http://www.microsoft.com/windowsxp/pro/using/howto/gettingstarted/multiboot.asp" target="_blank">http://www.microsoft.com/windowsxp/pro/using/howto/gettingstarted/multiboot.asp</a>