😕 Got a new set up in the shop, and me, being pretty crap with computers, I'm struggling getting the monitor right.
The new set up stretches images vertically, and i just need to bring things back to normal . There must be a way of altering the aspect ratio on the screen -any ideas please? Ta.

What OS?

In Windows 7 (probably similar for other Windows OS) it is Control Panel > Appearance & Personalisation > Adjust screen resolution.

Just play with settings till you get it right

Assuming it is new and windows 7….

Control Panel >

Appearance and Personalization >

Display > Screen Resolution

You should have a play in there, probably want to change the orientation or the resolution by the sounds of things.

Have you tried Display Settings in control panel (or right click on the desktop), to change the screen resolution? Or play around with the buttons on the monitor.

Windows? XP?

The screen has a resolution (its dimensions in pixels).
Your PC is outputting a signal for a different resolution.

Right click on the Desktop, go to Properties, Settings and change the "Screen resolution" slider to the cirrect value. Done.

Thanks for all the help there chaps! GrahamS' solution did it, cheers, mate!