Roger - Did you disable device 29 (in bios) before reinstalling? Then after you reinstalled Windows, did you insure that the DVD device was empty when you attempt to reboot. Also, if you have anything "hooked" up to the unit - disconnect them and see if this still happens.
Forgot to mention - after you have reinstalled Windows, re-enable the device 29 in bios. After this install you antivirus followed by the drivers and then the Service Packs and Windows updates. After all this has been completed - then reinstall you applications one at a time and reboot between each application and updates for each application.
Long and tedious problem.
Oh... After you install the Windows Service Packs, disable all USB devices so that Windows can "acquire" and install the newest USB 2.0 drivers. IF you don't do this, many times the USB connection remains at version 1.1.
Keep us informed.
Edit: Rather than "DISABLE" - I really meant Uninstall. Disabling it will not work for what is intended.....