How do I clean install Windows 7 upgrade to new mac?

Hello, I have kind of a complicated question...

Is there a way to install Windows 7 Professional Upgrade as a clean install to Parallels? I purchased the Windows 7 Professional Upgade as part of the "Ultimate Steal" student discount program which requires that I own a copy of Windows XP or Vista. I do own Windows XP.

Here's my situation:

I have 2 macbook pros. One very old (2007 macbook pro) with Windows XP Professional installed. I have the Product Key and ID but no install disc. (I lost it)

One new macbook pro (2011) and a bootable windows 7 professional upgrade iso (and have it burned to a DVD as bootable). I have an authentic product key and product ID that microsoft emailed to me. I ordered a backup installation DVD but that won't come for a few days (hence why I made the iso a bootable DVD)

So technically I own Windows XP (on one mac) and want to install a clean version of Windows 7 Professional on a new mac. Anyone know how to do this? When I try to install Windows 7 using the iso or the DVD Windows (in parallels) tells me I need a prior version of windows installed.

Your help is greatly appreciated!

David