I have had my MacBook Pro for almost 4 years now. How do i permanently delete my deleted files?

Question

I have had my MacBook Pro for almost 4 years now. How do i perminantly delete deleted files?

Answer 1

Your situation is not good, then. You will need to erase your hard drive and start anew. Boot from your installer DVD for the OS X version you have installed on it.
I hope you have backups because it's not likely you can backup at this point.
Clean Install of Snow Leopard
     1. Boot the computer using the Snow Leopard Installer Disc.  Insert the disc into the
         optical drive and restart the computer.  After the chime press and hold down the
         "C" key.  Release the key when you see a small spinning gear appear below the
         dark gray Apple logo.
     2. After the installer loads select your language and click on the Continue
         button. When the menu bar appears select Disk Utility from the Utilities menu.
         After DU loads select the hard drive entry from the left side list (mfgr.'s ID and drive
         size.)  Click on the Partition tab in the DU main window.  Set the number of
         partitions to one (1) from the Partitions drop down menu, set the format type to Mac
         OS Extended (Journaled, if supported), then click on the Partition button.
     3. When the formatting has completed quit DU and return to the installer.  Proceed
         with the OS X installation and follow the directions included with the installer.
     4. When the installation has completed your computer will Restart into the Setup
         Assistant. Be sure you configure your initial admin account with the exact same
         username and password that you used on your old drive. After you finish Setup
         Assistant will complete the installation after which you will be running a fresh
         install of OS X.  You can now begin the update process by opening Software
         Update and installing all recommended updates to bring your installation current.