Disable Recent Documents in Windows

 Through Registry tweaking:
(Take a backup of your registry since incorrectly editing it, might damage windows)

• Click Start > Run > and type “regedit” 
• Find and go to HEKY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
• In right panel create a new Binary Value and name it “NoRecentDocsHistory”
• Give it value of 00 00 00 01
• Close registry editor and restart your computer

Through UI:

• Click on Start 
• Right click on the picture or your name.
• Click Customize.
• Select the Advanced Tab
• UnTick at bottom: List my most recently opened documents