Windows 2000 error, file missing or corrupt

Hi there, I have had my laptop for about 1 year now - I bought it off of ebay so I don't have any of the "original" floppy disks or cd roms for it. I tried to use it yesterday and I get a black screen that comes up with an error message. No matter what keys I hit or anything I do makes a difference. I just get the same message and I can't get out of the screen at all. Below is a copy of the message. Also I'm not really experienced with laptops so if anyone can help me in easy terms that would be great. Thanks Windows2000 could not start because the following file is missing or corrupt \WINNI\SYSTEM32 start up option for windows 2000 press F8 You can attempt to repair this file by starting windows 2000 setup using the original setup floppy disk or CD-ROM Select R at the first screen go start repair.