smorizio :
http://www.howtogeek.com/186775/how-to-download-windows-7-8-and-8.1-installation-media-legally/
use a usb stick and microsoft iso to usb tool make a new usb boot disk. you need a 8g usb stick. the boot disk will be clean of any of the old disk errors. after you install the os onto the new drive and a anti virus software plug in the old drive and copy your data over. if the drive and windows is bootable now use google drive and back your files to the cloud.
Hopefully he has a working pc to do this on, I wouldnt touch the thing till he had the second hard drive and just try to do a drive to drive copy if possible. He could also use a tool like clonezilla to make an image of his disk and restore it later that way.