Windows 8 released but still in beta and the best way of testing an operating system that is still in beta is to run it on a virtual environment. Not running a VM on VMware or Virtual PC, or Virtual Box, but a VM in VHD format that runs natively and directly on a physical machine without a hosting system, namely Native VHD Boot, introduced first in Windows 7.
Native VHD Boot is also by far the best dual boot method to run two Windows systems without messing around with the partitions. And here is how, which is pretty much identical to this.
Step 1: get installation media ready
Follow this post if you haven’t.
Step 2: prepare your VHD
1. Click on Action from the top menu, and select Create VHD.
2. Specify the location and the size of the VHD file. Be sure the free disk space is big enough to host the maximum size you put in VHD.
3. Click OK.
Step 3: boot to Windows 8 Consumer Preview bootable media
Follow the installation wizard until you get to the point where to select the partition to install the OS. Hit Shift + F10 to bring up a Dos prompt window.
Type diskpart and press enter. Then,
DISKPART:>select vdisk file=d:\vms\win8preview.vhd
Note that the driver letter may change depending on your own computer setup.
Exit the Dos prompt window, and refresh the hard drive list to have the new VHD disk populated.
Highlight it and click Next to carry on.
After a few reboot, the highly appreciated dual boot screen window nicely shows up without you fiddling with the BCD settings.
How to change the boot option
You can change the boot option on both Windows 7 and Windows 8. Go to Startup and Recovery from System Properties.
When you are done with the test
And you wish to not only delete the VHD file but also clean up the boot entry in the boot menu. Check out this post that might help you accomplish this. But what I found is that unless you need to create another VHD for native boot you probably can leave the obsolete entry there but set the wait time to 0 so that the system automatically boots into Windows 7 without prompting with choices. The VHD file can be easily and permanently deleted when booting to Windows 7.