Dual Boot Windows XP and Windows 7

I have Windows XP 32 bit version installed and attempted to install Windows 7 64 bit version on a second drive (my computer supports 64 bits). Everything went ok until Windows 7 attempted to restart the computer to complete the installation. Basically, the computer re-started, the dual boot screen came on, and when I selected Windows 7 an error came on and would not restart. Unfortunately, I did not write down the exact error, but had something to do with 32 boot ini missing. I tried to re-install it a few times, and the same thing happened. I then Windows 7 and got rid of the dual boot screen. I would like to do it again, but want to do it right this time. FYI - the BIOS shows the second hard drive, but it is not shown as a drive that can be bootable. I am not sure if this is the problem. What would happen if I just unplugged my C: drive, and installed windows 7 on my second drive? When I plug my C drive back in would it dual boot, or ignore my second drive again. My second hard drive does have a letter assigned to it under disk management. Thanks for your help!

Yes to both. The hard drive was brand new and I initialized it under disk management. Now that Windows 7 is not on it, I just you it as a back up drive. Ii is Disk 1 (Disk 0 is my c drive) and says it is online.

If you can select the boot disk at POST, disconnect the disk that has Windows XP 32 installed while you install Windows 7. Once installed, reconnect the Windows XP disk and make it your boot disk again. Select the Windows 7 disk whenever you want to boot it at POST.

Power On Self Test (POST). What motherboard do you have? Unless it's an old or inexpensive motherboard, it should allow you to select a boot device from the BIOS boot menu. This is more convenient than having to set the bootable hard disk whenever you want to boot an alternate OS from another hard disk.