I try doing this:…..?

Windows could not start because the following files is missing or corrupt
\WINDOWS\SYSTEM32\CONFIG\SYSTEM or \WINDOWS\SYSTEM32\CONFIG\SOFTWARE

Insert and boot from your Windows XP CD.
At the first R=Repair option, press the R key
Press the number that corresponds to the correct location for the installation of Windows you want to repair.
Typically this will be #1
Enter in the administrator password when requested
cd \windows\system32\config
Depending on which section was corrupted:
ren software software.bad or ren system system.bad
Depending on which section was corrupted
copy \windows\repair\system
copy \windows\repair\software
Take out the CD ROM and type exit

How can I get administrator password when requested?…….thanks

I restarted my pc and got this error message "Windows could not start because the following file is missing or corrupt : \WINDOWS\SYSTEM32\CONFIG\SYSTEM
You can attempt to repair this file by starting Windows Setup.
Select ‘r’ at the first screen to start repair."
Then I followed these steps :

Boot to the Recovery Console.
At the Recovery Console command prompt, type the following lines, pressing ENTER after you type each line:
md tmp
copy c:\windows\system32\config\system c:\windows\tmp\system.bak
copy c:\windows\system32\config\software c:\windows\tmp\software.bak
copy c:\windows\system32\config\sam c:\windows\tmp\sam.bak
copy c:\windows\system32\config\security c:\windows\tmp\security.bak
copy c:\windows\system32\config\default c:\windows\tmp\default.bak

My problem is after typing
copy c:\windows\system32\config\security c:\windows\tmp\security.bak then i press enter it says "the system cannot find the file specified" and so on the c:\windows\system32\config\default.
Please Help