My PC crashed four months ago with the classic blue screen and IRQ messages. I eventually got into safe mode and backup critical files(thank god !). The PC kept resetting so i had to reinstall windows. This was very problematic with the reinstall failing numerous times. Eventually i got win xp home reinstalled, but with two versions on the hard drive ?! So when i start up the computer i am offered two versions of win xp to run, i always choose the second. Checkdisk shows four clusters/segments which are unreadable or damaged. I think the best course is to replace my Hard drive. Was is the best way to do this ? buy a external HArd drive, backup(Is there a windows procedure for this) and then install a new hard drive and load everything onto this ? Also i have been having USB problems at the same time. Sometimes my pc does not detect a keyboard, the only way around this is start the PC with only the keyboard connected .