Can I just check if Vista and/or Windows 7 have been run on this computer before, this to ensure that it has the required system specifications.
Couple of things I would suggest if you are going to prepare another ISO;
Try another brand of DVD disk.
Try another burning software.
Try turning the burning speed down to either X2 or X4.
Use the Windows download tool or Rufus to make the ISO bootable.
third is network boot: atheros boot agent.
FWIW I tend to disable this feature as it doesn't help with the troubleshooting process, you cannot boot from it unless it has previously been configured to do so which involves significant work and specific hardware and software.