Solved resolution in desktop effects

[patch]

Hi my young grandson had a good bash of my keyboard, and now my desktop is bigger than my hdmi tv's screen, and scrolls left/right/up/down when moving the mouse. The desktop reverts to the correct size when I disable 'Desktop Effects' (Alt=Shift+F12).

Can anyone help with correcting this as I am very fond of the desktop effects?

[canadaist]

Menu > Tools > System Tools > System Settings > Display and Monitor > Size & Orientation
It might not just be size, it might be refresh rate, try auto, try a couple

[doktor5000]

It might be the zoom for the desktop if you can disable it via desktop effects.
Menu > Tools > System Tools > System Settings > Desktop Effects > All Effects > Zoom
meta key + 0 should also reset the zoom, like in a browser with Ctrl+0.

[patch]

Thank you doktor,
I removed the tick from the zoom box, and it is fine.

[patch]

thank you also canadaist