I was actually able to use this method to get my boot camp installation working.

After I had copied driver.cab and renamed the copy to sp2.cab parallels allowed me to boot windows instead of displaying the unable to open image error. Neither the keyboard or mouse worked at first, but after about a minute the keyboard started working. Since the mouse wasn't working I decided to try installing parallels tools to see if it would fix it. Well after selecting 'Install Parallels Tools...' from the 'Actions' menu the dialog that would usually display when first booting windows during an express install appeared. The parallels tools were automatically installed and ever since windows rebooted after that everything now works!