Handy when working with Microsoft Surface: install your development environment on a separate VHD that you can boot as your physical machine (Microsoft Surface SDK does not like being run in a Virtual Machine):
If you accept the constraints described above, I propose the following procedure, which I think is the easiest way to install Windows 7 on a virtual disk in multi-boot
Note: Within the VHD you can still access all the files on your physical HD.
–jeroen
via: How to install Windows 7 on a virtual hard disk (VHD) in 10 steps – Guides & Tutorials.