Cannot get to safe mode. No original XP CD furnished from supplier. All legal.
That is not enough information to receive useful advice.
Have any hardware oriented changes been made to the system since it
worked? RAM, video card, storage (hard disks, USB devices), hardware
drivers, device drivers?
If you can only boot in Safe Mode and are seeing a BSOD, choose the
option:
Disable automatic restart on system failure
Then you can see the BSOD.
Here are some BSOD blue screen of death examples showing information
you need to provide:
http://www.codinghorror.com/blog/images/Windows_XP_BSOD.png
http://techrepublic.com.com/i/tr/downloads/images/bsod_a.jpg
Send the information pointed to with the red arrows (3-4 lines
total). Skip the boring text unless it looks important to you. We
know what a BSOD looks like, we need to know the other information
that is specific to your BSOD.
If you don't have a bootable XP installation CD, can you borrow one
and make a copy?
If no bootable XP installation CD is available, create a bootable XP
Recovery Console CD and when your system is booted on that, we can
proceed:
You can create a bootable XP Recovery Console CD when no XP media is
available:
http://www.bleepingcomputer.com/forums/topic276527.html