|stjam the mbr is not in any windows folder.|
the correct answer to restoring the mbr is go into recovery console and use the utility fixmbr.
But that is not your issue. It was not the mbr causing your issue. Additionally you put a new mbr on a different drive [now c:] with your new installation.
If you want your first install back you need to do the following;
disconnect the drive the new installation of xp is on.
set the bios to boot the xp dvd
go into recovery console
run the utilities fixmbr and fixboot.
exit and reboot.
Do you come up on windows?
if not your next step is a repair install of xp not a new one. This will refresh the OS files and not mess with your data.
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