There is a lot of VHD integration in Windows 7 and Server 2008 R2.  We already showed how to boot from VHD but you can also mount a VHD from within a Windows 7 / Server 2008 R2 environment.

Open up Disk Management, you can Right-Click on Computer and choose Manage and then select Disk Management to do this.

Right-Click on Disk Management and choose Attach VHD.

Enter the path to the VHD.  You can choose to mark it Read-Only as well. Click OK.

The drive will mount and display in Disk Management.  You’ll notice the disk icon is also blue to help you distinguish it as a mounted VHD.

To dismount, Right-Click the disk and select Detatch VHD.

You will be given the option to delete the VHD as well, but it is not the default.  Click OK to detatch.

For more information be sure to check out the Windows 7 resource page on Technet.com