You may be having a problem with your boot files being in the correct order. When I put Windows 7 and and XP on this computer I used this guide and it helped a bunch hopefully I helped out a bit! Make sure read all the steps because some are outdated and won't need to be done, i.e. Downloading Windows 7 and burning it; given you have an install disc already.
I recently formatted the second partition on my Asus Eee PC 1000HE (it came with the main drive partitioned twice) to install Windows 7. It worked like a charm. I then tried to shrink the partition using the Win 7 disk management feature, and somehow changed all the disks to simple disks.
I still get the option to boot into either Win 7 or XP when restarting, but only the Win 7 option works. I can get to the XP splash screen with the loading indicator, but it blue screens before fully starting.
My question is this:
Can I reconvert my XP partition back to a primary partion so I can use it again without reinstalling? Or is that even necessary?
I can explore the xp partition just fine, so I wont lose any data.