Windows missing file error

[Matrs13]

When i try to boot my computer up i get an error. The error says Windows could not start because file is missing or corrupt "\Windowns\System32\Config\System". Then it says "you can attempt to repair files by starting windows setup using the original setup cdrom"..........so i threw in the windows disk, let it load up and i push r to repair it, but then i get this thing asking for my windows instalation and i type in 1. Then i cna type other stuff but i have no idea ware to go to fix this file someone please help

[patio]

After you are in the Recovery console you want to type in sfc /scannow and hit Enter...notice there is a space between sfc and the /scannow command...

[Matrs13]

Tried and it said invalid command. It says i can do these things when i type in help like it tells me........
ATTRIB
BATCH
BOOTCFG
CD
CHDIR
CHDSK
CLS
COPY
DEL
DELETE
DIR
DISABLE
DISKPART
ENABLE
EXIT
EXPAND
FIXBOOT
FIXMBR
FORMAT
HELP
LISTSVC
LOGON
MAP
MD
MKDIR
MORE
NET
RD
REN
RENAME
RMDIR
SET
SYSTEMROOT
TYPE

It says i can do all these commands so plz help