1. Insert your MacBook restore DVD 1 into your computer and restart.
Hold down "C" as the computer boots so it will boot from the disk.
2. Select your language and click "Continue."
3. Click "Options" at the "Select a Destination" window.
4. Choose "Erase and Install." Click "Continue."
5. Choose "Basic Install." Click "Install." Once the install is complete, your MacBook will be restored to its factory settings.
How to Restore My Macbook to Factory Setting | eHow.com
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