How to: Modify the Hide files of types list in Explorer 'Options' dialog box.

Solution:

Currently there is no way to edit, add, or remove a file type to or from this list.
NOTE: To view this list, select the 'View' menu, select 'Options...', and click the 'File Types' tab. Select the 'Hide files of these types' radio button, and look in the list box, scrolling to view more.