Regarding VHD File
To open a .VHD File in Windows 7
Virtual Hard Disk (.VHD) file are used by Virtual PC and Virtual Server, and created by Windows Back-Up when you make a system image back-up. If you ever need to access a file contained within a .VHD you can do it using the Disk Management Tool built into Windows 7. Just follow these steps:
1) Click Start, Right Click Computer, and then click Manage.
2) Expand Storage and then click Disk Management.
3) Click the Action Menu, and then Click Attach ,VHD
See Pictures and Instructions Below: