Windows CSS/HL2 issue

ok a mate of mine jumped on my comp and played with my gfx settings. now whenever i go to play either of them my monitor comes up with a msg saying that the monitor is out of range or sutting like dat.

im guessing he tried to stick my res up over the monitors limit totally screwing it. anyway i can fix it?

 

yeah, delete one of this config files or reinstall the game.. lol

 

tried deleting configs and still no go. and im not really wanting to reinstall as it takes to long ;(

 

You can change it in regedit, at work right now so can't get the reg key to change .