I recently tried to dual boot Ubuntu 12.04 with an old Windows XP System. Instantly after installing upon start up I get "Disk Read Error" then the whole ctrl + alt + del thing. I don't get a grub menu or anything. Oddly, if I keep the usb in that I used to install Ubuntu and boot from that USB it'll bring up the Ubuntu grub menu. It'll work if I choose Ubuntu but if I choose Windows it goes back to the "Disk Read Error". I've tried countless solutions to repair the MBR. I've tried:
Windows XP Recovery Console
None of it has fixed the issue and I installed Ubuntu following the directions on a distro site. One might think it is installed to the USB since it requires the usb to boot into Ubuntu but that is incorrect. Once booted I can remove the USB and it works fine. Also, I have reformatted the USB and wiped it completely and it still requires me to boot from the USB to load the Ubuntu grub.
I want to get my Windows XP back, and I'm definitely removing Ubuntu from that computer and never trying to dual boot again. Too much hassle. I do not wish to reformat the entire hard drive and reinstall Windows XP. I need this fixed ASAP.