The Recent Docs menu can be easily disabled by editing the Registry. To do this go to
GO TO
START>RUN type regedit
Then go to his key
HKEY_CURRENT_USER\Software\Microsoft\ Windows\
CurrentVersion\Policies\Explorer.
Now in the right pane, create a new DWORD {to create this right click on the right pane & then new>DWORD}valueby the name: NoRecentDocsMenu and set it's value to 1.
Restart Explorer to save thechanges.