Aspect Ratio Help?

Hello. ^_^ Does anyone know how to reset the aspect ratio on my computer? It’s an HP laptop PC with Windows Vista. It’s happened before, but I can never remember how to fix it, and DH is at CES, so no help there.

If you’re wondering what I mean by aspect ratio, everything on my screen is now stretched out to the sides, and squished down from the top, distorting everything on my screen.

I used the computer this afternoon, during which I did download a Windows Defender update, then put the computer to sleep while I ran errands. Then when I opened it up tonight to use, the screen reset all of a sudden to the distorted view – it’s most annoying.

Thanks in advance for any help you can provide. ^_^

~Marilee