Use the first R and go to the Recovery console

To start the Windows Recovery Console, use one of the following methods: • Use the Windows Setup floppy disks or the Windows CD-ROM to start your computer. At the "Welcome to Setup" screen, press F10 or press 'R" to repair.
http://support.microsoft.com/kb/314058

Recovery Console commands
http://www.microsoft.com/resources/d....mspx?mfr=true