I wanted a windows installation where I could write my book and escape from the apps of my everyday windows operating system. You will find plenty of articles about dual boot with Linux, but I couldn't find one on how to dual boot two windows installations.
In hindsight, after talking to one of my colleagues, there is an easier way to do the same thing using just the windows boot disk and navigating through the UI wizard. This article is still relevant if you want to understand what the wizard does, if you want complete control, or if you want to upgrade the OS in just one of your partitions.