//Why are you still using XP when support is about to run out.//
Not a helpful question. The threadstarter has what they have and is not here to have judgements made on them.
By all means suggest that they upgrade but at least tell us all what the upgrade CD is going to cost them, please.
Oh, I forgot, they can't set about an upgrade until we've fixed the boot failure situation. Let's focus on that, shall we?
@Booyaa99
Do you see a steady light or any flickering on the HDD activity light?
If not, can you hear any motor noise or other sounds from the HDD?
Are there any dents, scratches or outward signs that the laptop has been dropped?
As per vascop's post, try booting from the WinXP master disk. If you can get it to progress as far as Windows Safe Mode, you should be able to ascertain whether the C: drive is at all operational. If it is, you might be able to run a virus scan and see if any software or user data is intact.
HDDs can get into a state where they refuse to boot but the data is recoverable. A new HDD could be as little as £30 and your local PC repair person will have special software with which to do the data recovery. After that, you can retain the unbootable drive as a slave unit or, if you don't trust its reliability any more, stick a drill through it and take it to the recycling yard.