Hi,
Many times this error is caused when the computer is attempting to boot from a non-bootable floppy disk or CD-ROM. First verify that no floppy diskette or CD is in the computer, unless you are attempting to boot from a diskette.
This error has also been known to occur when a memory stick is in a card reader and the computer is attempting to boot from it. If you have any card reader or flash reader make sure that no memory stick is inside the computer. Additionally disconnect all USB drives, cameras, ipods, iphones, etc. from the computer.
Resolution:
Repair the file system boot sector or the master boot record (MBR) also try to fix the Boot file.
Refer :
Description of the Windows XP Recovery Console for advanced users