using the 'shell hack' you can make it seem that way, but your os would still be the foundation of the boot
don't take this wrong, but i don't think you were doing it right. if you did the shell thing, you might've been in the wrong registry key. also alot of changes are system, not per user. as you're on xp just use hardware profiles and everything will be good. as i'm on 7, and they removed profiles since vista, i have to dual boot.
good program if you're not too comfortable with registry tweaks etc...
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