awhatley wrote:
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I've got my Vista disc and my old XP discs and would like to try installing
again, but I can't use it because all the computer will recognize to boot
from is the 3.5 diskette drive...

This has nothing to do with Vista. The BIOS of your computer determines
what hardware devices will be available to boot from.

To fix the problem you need to enter your BIOS config utility during the
next boot. The usual way is to hit the DEL key during the boot.

Once in the BIOS config, you will be able to change the order of boot
devices.