change settings snafu

Although I'm not a newbe to comps I can still screw things up royal. I was putting in a game that told me to go to notepad and access "change settings". So I did. Set the resolution from 600 by 400 to 800 by 600 or something. Clicked on ok. Told me to choose exit or continue. Like a tree stump I click exit. next screen is unrecognisable stuff. I did however, get to the c:\> prompt. Hope thats right. My question is; How the heck do I fix this one. How do I change the setting back to its original. Backup disk lost. Could use telephone support. If you reply I e-mail you my phone no. so we can talk. If not thanks anyway for your help

All you should need to do is to run SETUP in your Windows directory. This will allow you to change your settings back to where they were.