PC not Booting- Windows XP

Hi,

Just a few days back when i was surfing the net and the computer suddenly restarts and I get this Blue Screen and at the end it says,"Beginning to Dump Physical Memory". I restarted the computer and then no error message. The next day when to try to ON the computer i get this PXE-e53 No File Name Received and with some realtek external Controller stuff on top. I shut downed the computer. Next day no errors. I started surfing the net about this PXE-MOF problem and found out that The Boot Device Priority in BIOS would solve it. I tried it and it was fine for that time only.

Next day I ON the PC -same error, restart it(works) and again surf the net and found out that I have to Disable NIC configuration and check the cables of HDD. When i went and searched in the BIOS and couldn't find NIC. But did find a Boot To Network in the Boot Tab and i disabled it. It removed 'Ethernet' from the Boot Device Priority. I save it and restart the PC and this time I get a message " Boot Failure. Press Any Key To Continue". I restarted and enable Boot to Network in BIOS and I get the PXE error again.I Restarted the PC and restored Defaults in BIOS but same error(PXE).

Next day I asked my Dad to open the PC and check the cables. He opened it and removed the two cables attached to the HDD (Hard Disk Drive) and then he removed the dust from the HDD and put everything back into place. We ON the PC and it finally worked.................... I go to the bedroom and when I return I see this irritating Blue screen again ( the same one at the start). We restart it and no effect- I get the same PXE error. When i put a usb and on the computer an error comes saying," Disk Error Please click to Restart "

The thing is I cannot replace or format the hard disk since it has some important files and I don't have backup for them so what do I do???

Would doing a repair using Windows XP CD work? or would changing the OS work?

Please tell me what to do

I want to know what is causing it and what do I have to do to repair the fault and what should I do to prevent it in future?

My Computer Configurations

Windows XP Professional Service Pack 2

2.00 GB Ram

Intel Dual Core 2 e7400 2.80 GHz

PLEASE HELP ME


I also got an answer saying that

" You have to remove your hard disk and connect it to friend's PC (working) then backup or copy your files to friend's HDD. Then format your HDD in NTFS format.

- Now leaving your files on friend's HDD, connect your computers HDD back to your PC.

- Boot your PC, press F11(whatever key to setup BIOS) and then restore default settings.

- Do a fresh installation of windows.

- Configure it properly according to your usage.

- Then again remove it and connect it to previously connected friend's PC. Copy all your stuff to any other partition of HDD.

- Finally, again connect it to your PC, and its done.

NOTE : While connecting your HDD to your friend's PC make sure that you are connecting it in SATA 2 and not in SATA 1. As SATA 1 is primary port for booting OS"

would this work or else what should i do?

Im planning to change the OS only after receiving my files back. So please help