Install the older OS first. If you want to research this, type this at google.com or bing.com
HOW DO I INSTALL XP AFTER WINDOWS 7?
You'll find this discussed at many sites.
i have windows 7 home premium as my main OS on my C drive.Created a partition on my extra internal D drive (named I: in win 7).and installed XP pro on it.Then my system wouldnt give a choice of boot at startup just would boot xp. Used windows 7 cd and repaired windows 7 and it now boots into windows 7 but startup doesnt give me a choice of OS to boot into.
ANY advice would be appreciated on how to boot into XP when i want to but still allowing win7 to boot as my OS of choice.
Thank you in Advance