Windows XP can't boot up

[JuPPiE]

yo all.
my winxp cant boot up normally, so i have to press F11 a few times, untill boot menu opens, and i select my OLD windows XP from the old hard disk from old computer (than god i still have this hard disk!!!)
i get 0x7b errors in a blue screen every time i try to launch the xp in safe mode / normally.
please help me fix that (i just hope the solution doesnt contains the word 'format disk')
i have some windows xp disk,it isnt a geniue windows xp but i still think i can and try repair install...
pl0x help ASAP

[Marc2984]

If you got a harddrive from another computer, it could be true that he won't boot. Did you try booting in safe mode?