Gateway notebook recovery disk nv78

You can buy one here

http://us-store.gateway.com/rcd/

should have created one when you got it.

On most laptops and notebooks that don't come with a Windows recovery disc there is usually a hidden partition on the hard drive that contains that information and you would be able to restore your OS to factory condition or do a Windows repair.
If you go to the support page at Gateway you can find out how to access it.