A few questions:
1. Is your copy of Windows a retail full install copy or is it some other version?
2. Did you run a full clean install, formatting the drive before you ran it or did you run an update install?
3. On the other Windows install, I assume that as it is on the pc from which you booted the first disk that you have set the optical drive as the first boot device and again, is it a full retail version?
4. Do you know that it is a bootable disk, if you are unsure try booting from it on another pc.