You can read the directions for use in the Users manual on page A 15 in the Appendix.
it starts off with this introduction on the Recovery partition
[i]Windows Vista Software Recovery
Using Hard Disk Partition
The Recovery Partition includes an image of the operating system, drivers, and utilities installed on your Notebook PC at the factory. The Recovery Partition provides a comprehensive recovery solution that quickly restores your Notebook PC?s software to its original working state, provided that your hard disk drive is in good working order. Before using the Recovery Partition, copy your data files (such as Outlook PST files) to floppy disks or to a network drive and make note of any customized configuration settings (such as network settings).[/i]
If you do not have your Users Manual you can download it from here
http://support.asus.com/download/download.aspx?SLanguage=en-us
If you want to you can buy a Recovery DVD from ASUS which generally has a minimal cost which covers Postage and Handling but as that is a matter with ASUS you need to take it up with them directly. ;)
Col