Ahh, I see, to a new winXP install, rather than just a new hard-drive. You could try installing mint4win on the new computer, then overwrite with the backup you made earlier. This way the bootloader would be corrected, and hopefully you'd have the old files in the new computer. I say hopefully, because I don't actually use mint4win, but if you're backup and restore methods are sensible, you shouldn't have any problems.
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