Unable to reinstall OS X Mavericks or Snow Leopard

My 27" imac crashed and would not restart. It all started when I was trying to run a time machine backup and I received a message saying that there was an error with my backup drive. I tried several times to backup to an alternative external drive but each time it failed. I then manually backed up all of my files to my alternative HD. I was almost finished when the computer crashed.

I booted up in recovery mode and ran disc utility. There was an error on the imac HD and I was unable to repair it so I erased the memory. I then tried reinstalling OS X but it takes about 13 hours to run and each time I go back to it, it is back to the recovery page.

I then tried to use the snow leopard disc that came with the computer. I erased he HD again and ran the install program several times but I am alway met by the same message... The installer could not copy the necessary support files. Click restart to restart your computer and try installing again. I have done this several times.

Any ideas or help would be appreciated?