bsod and now no windows boot up

so yeah earlier today i updated my gpu drivers from 158.22 to 162.18, played some games, and got a blue screen of death. Now when i start the computer, i can access the bios, but cant launch windows. It says that the following file has been damaged or doesnt exist : ///config/system ( i only remember the last two parts, there was like 2 more parts before that). It also says i can repair it if i insert the windows cd and press ''r''. Now, i dont know when to press r...so i would like some help here. I would also like to know what aare the effects of repairing this folder. Is it going to format my computer? Thanks a lot for helping, and sorry for not knowing what to do, its just that its the first time this happens to me.

Boot up in safe mode and do a System Restore. During bootup just keep tapping the F8 key until you get a dos menu. One option on it should be safe mode. This loads up bare bones basic windows. If the system restore doesn't work you can use this to uninstall the new driver and install the old one. If this doesn't work at all, then you'll have to use the windows os disk to boot up. Make sure your bios is configured to boot off of the CD/DVD drive. Then just pop the disk in and restart the machine.fynne

ok so now i pressed r on the windows menu, then i get this :

Press exit to quit the commands invite and restart the computer

1: C:/windows

on wich windows xp instalation do you want to open a session
(press enter to cancel)?

Now what do i do?