Hello Neal, and welcome to Seven Forums.
Windows 7 already has a
Open command window here item in the context menu of folders and drives. You would need to press and hold
Shift and right click on the folder or drive to see it by default.
Open Command Window Here
The tutorial below will show you how to not have to press Shift to be able to just right click on a folder or drive to see
Open command window here in the context menu.
Open Command Window Here - Add or Remove Shift + Right Click
In addition, the tutorial below will show you how to add
Open command window here as Administrator in the context menu of folders and drives to be able to open a elevated command prompt at that location.
Open Command Window Here as Administrator
Hope this helps,
Shawn