Mac Pro not detecting Windows install DVD
I figured out a workaround that is probably more unconventional and useless to most people.

The things I used:


Clean Lion installer
A random Windows 7 Pro x86 ISO found online and burned to DVD
Doner install machine (MacBook 7,1)
Target machine (MacPro1,1)
Empty 128GB SSD disk (any disk smaller than target will work)
HDD cloning machine


The steps:


Swap the disk with all my personal files out of the MacBook and install an empty disk (must be smaller than the target disk).
Made a clean installation of Lion on the disk.
Ran through bootcamp on the MacBook (the DVD I burned earlier worked perfectly which is further evidence of something really weird interfering with detection of the Windows install DVD on the Mac Pro). I reached the Windows 7 desktop. It's important to not install any drivers as this could make the installation useless when moving to the target machine. Windows will automatically install drivers for a few things which will later need to be disabled.
Removed the SSD disk and cloned it to the target 1TB 3.5" HDD with a cloning machine. Installed the 1TB HDD in the Mac Pro.
Booted Windows 7 Pro x86 (only worked in safe mode)
Disabled drivers for non-critical hardware and unplugged all peripheral devices except mouse and keyboard). This fixed the boot issues with normal Windows and now I could boot normally without needing to use safe mode.
I haven't done this yet but I need to resize the Windows and macOS partitions to use the entire disk (right now I have 2x64GB partitions). This is doable but a little harder since Disk Utility will not resize/interact with partitions with a Windows partition on the disk. This is probably because of the different file system. Then, I just run the bootcamp 4 support drivers and everything should be normal.


Hope this helps someone though I doubt it because most people don't have access to the equipment that I used. There are other methods involving what appears to be cloning virtual machine images to HDDs but I haven't attempted. This solution seemed easier to me.

The problem still puzzles me. The Mac Pro DVD drive works fine as it is able to play movies and install software. However, it just gives a finder popup for a "blank DVD" with the Windows install DVD inserted. On the other hand, my MacBook 7,1 recognizes the DVD perfectly. I didn't have a spare IDE DVD drive to try in the Mac Pro but I think the drive is fine. Generally, I've found the Mac Pro to be subject to more issues than other Apple products because of its ability to be customized. I suspect this is just another example. This Mac Pro should have been easily able to perform this bootcamp installation as it is officially supported to run bootcamp with Windows 7 x86.