This tutorial discusses the steps for changing the number recent documents displayed in PowerPoint 2011 for Mac. Mac users can change the number recent documents using the option available as part of PowerPoint 2010 Preferences.
Click the PowerPoint menu and select Preferences from the menu list.
In the Preferences window, navigate to General Options under General tab.
You can change the number of document displayed by specifying value for Display “X” documents in Open Recent. The maximum number of documents that can be displayed is 99. If you do not want to display the recently opened documents in PowerPoint 2011 then un mark the check box with label as Track recently opened documents.