The problem may not be the OS but the hard drive itself. My daughter came to me with a problem like this and when I tried to reinstall the OS, it kept crashing. So I formatted it and tried the install, same thing, so I tried to install a different OS and it failed at the same spot. The reason was that the hard had a physical damage on the disk and that was causing the problems. So you might consider, if you have one, replacing the hard drive and going through the steps, if it succeeds, then you have your answer, if not, then you have something else going on, but I bet it is a bad hard drive.