That's what System Restore is for.
A Toshiba Satellite laptop running Vista I was recently given crashed on me today. When it restarted, Windows updater started running, and at that point I noticed the screen resolution was off. When the computer turned on, I couldn't get onto the internet, and couldn't run diagnose and repair (although that problem has been fixed).
The remaining problem is my screen resolution: everything is too big. I went to try and change this in Display Settings, but allegedly I am already in 1024x768, and the only alternative (800x600) just makes the problem worse. After googling, I checked my DPI, which is 96, I'm guessing not the problem.
Anyone able to help?
Here's a picture of what I am looking at. Thanks!

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