Using Finder, take a look in the "Applications" folder for "System Preferences.app".
Is the application there?
If yes, can you open it by double clicking in the "Applications" folder?
If yes, but you cannot open it by double clicking in the "Applications" folder, try right+click and select "Get Info". A window should open giving you information about the program. At the bottom of the "Get Info" window under "Sharing & Permissions" does it say you have access?