|The Intel URL you are advised to visit no longer exists anyway, so ignore that.|
It looks like your computer's hard drive may have failed and needs replacing.
To check if it has indeed failed, test it with Seagate SeaTools for DOS.
Go here and click "Downloads": http://www.seagate.com/support/down...
Be sure to download "SeaTools for DOS", NOT SeaTools for Windows.
The download is an ISO file from which you can create a CD using IMGBurn from here: http://filehippo.com/download_imgburn/
When you've made the CD, boot your PC from it and the SeaTools for DOS utility will open. Select the appropriate hard drive and run the long/extended test on it.