Cannot boot from Windows 7 install DVD or USB

I'm currently running Mavericks 10.9.1 (clean install) on an early 2008 Mac Pro (3,1). My main HD is an SSD, I swapped out the stock super drive for a blu-ray drive, and I've got the four bays filled with other hard drives, one of which used to have Windows 7 which I could dual-boot from. Long, long story short, my Windows 7 install got corrupted, so I ended up wiping and formatting the drive from Disk Utility and set about re-installing W7.

I quickly found that I could not boot from my W7 Home Premium 64-bit install DVD (same one I previously used to install W7).

I've tried the following options:

- using Boot Camp Assistant to partition and initiate the Windows installation

- manually selecting the Start Up disk in System Prefs - the install disc always shows up

- holding Option key at start-up

All of these options produce the same result: I get to the boot selection screen with my Mavericks HD, Recovery, and a Windows CD icon, and an EFI Boot (also CD icon). If I select the Windows option, I get the grey start up screen, with the Apple icon, and it just hangs indefinitely. I can hear the optical drive eventually power down and it just sits there. If I select the Boot EFI option, it immediately freezes on that screen.

I've also tried burning the W7 install disk iso to a flash drive (both manually using Disk Utility, and using the Boot Camp Assistant with the plist file tweak) but Mavericks refuses to recognize the flash drive as a boot source.

I've tried downloading other Windows 7 64bit images, both with and without SP1, with exactly the same results. One time instead of the hanging Apple icon I got a "prohibited" icon - circle with a slash through it.

I've disconnected all USB/firewire peripherals, reset PRAM, fixed disk permissions, tried just about everything I can think of.

Do I need to downgrade to an earlier version of Mac OS X, or of Boot Camp Assistant? Could this be an issue with the blu-ray drive?

Any assistance or advice would be most appreciated.