XP won't load past OS system selection

Hi,

My friend's computer which I am attempting to fix won't boot past the OS system selection screen, just goes to a black screen. It stops at (as I have found to be quite common) isapnp.sys when booted in Safe Mode.

I downloaded WindowsXP-KB310994-SP2-Pro-BootDisk-ENU which I made into a bootable disk and then attempted to boot off it.

However, after going to the blue screen and says "Windows Setup" and along the bottom says Windows is loading files. Then it says starting Windows.
However this is where I get the blue screen which says

'A problem has been detected and windows has been shut down to prevent damage to your computer.

If this is the first time you've seen this Stop error screen, restart your computer. If this screen happens again, follow these steps:

Check for viruses on your computer. Remove any newly installed hard drives or hard drive controllers. Check your hard drive to make sure it is properly configured and terminated. Run CHKDSK /F to check for hard drive corruption, and then start your computer.

Technical Information:

*** STOP: 0x0000007B (OXF79B9524, 0xC0000034, 0X00000000, 0X00000000)"

Any help to do with this would be really helpful, thanks

Charli