how can i do a system restore?

easiest thing for you to do is to get a copy of xp disk when promted click to boot from cd then wait for the screen to come up select repair windows then you will come to a command screen type in chkdsk /r this will repair any damages done to windows then when this is finished type bootcfg /scan this will check to see if the boot sector is ok if it tells you it is unable to scan due to it being damaged you can then type fixboot to repair the boot sector.remove the cd and type exit
when the pc reboots push f8 this will give you the option to run in safe mode then whilst in safe mode scan the pc for virus's and delete any infections found. good luck.
also get yourself a decent anti virus please do not use norton use avg or avast they are both free and very good also use malwarebytes as this will clean up all your malware and spyware

PC MAN
November 2009