Windows 7: Moving Location of Shell Target Folder Uneditable

I've searched this forum (and the web) and haven't found the answer to this problem. I have a relatively new (and clean) install of Windows 7 on several computers. I want to move the Public Videos folder to another disk. If I right-click on Public Videos in Windows Explorer and then Properties and bring up a Properties box, there are 6 tabs at the top. One is Location which *appears* (and the text describing the dialog implies) to be editable. On my computers - and in fact, all my Windows 7 computers - this target folder text box is not editable. In addition, there are no buttons such as "Move Target Folder" or anything like that displayed.

What am I missing? Does a registry key need to be changed to allow editing of the text box? I just want to change the Public Videos shell folder from "C:\Users\Public\Videos" to something like "D:\Users\Public\Videos".

Thanks in advance.

I changed the title of this thread because I now have more information on my problem. I can move the location of my personal user shell folders (Musci, Videos, Pictures, etc), but I can not move the Public user shell folders in a similar way. When I go to the Properties tab of my personal user shell folders, I have the "Restore Default", "Move", "Find Target" buttons. However, these buttons do not appear from the similar Location tab of the Public user shell folders - although the dialog on the tab implies you can change the target. Anyone know why or how I can move Public shell folders to another drive? Thanks once again.