Defragment and chkdsk doesnt work

insync with the thread
http://forums.majorgeeks.com/showthread.php?p=1352902
where the forum helps me to remove a deadly virus

my defregment service is not working
neither can i run chkdsk (it runs but with no effect)

kindly help me restore the same

i have over written windows but not instaled sp3 yet

 

i do have an o&o de fragmenter (fortunately licensed) which was disabled in due course of the viral infection which has now started working

however the windows defrag service doesnt kick off
need help with that

 

i mean to say my o&o defrag is working

when i start windows defrag it gives an error

""MMC cannot open the file c:\windows\system32\dfrg.msc

this may be bcoz the file doesnt exist, is not a MMC console, or was created by a later version of MMC. this may also be bocz u do not have sufficient access rights to the file""

 

Let's start by asking for some system specs.

How big is your drive and how full is it?
What sort of computer is it - Laptop or desktop
What are your power settings?

Do you have your Windows XP CD and have you run System File Checker?

 

i have a 160G hdd which is around 60% full

system spec
4300 core 2 duo
2 x 1 gb 800mhz ram
160gb toshiba sata hdd
samsung dvd writer
p965 neo MSI mobo
nvidia 8500gt 512mb graphic card


i do have windows CD
how do i run the System File Checker???