desktop icons too small xp

Hi the icons on my desktop have become smaller and the desktop does not completely fill the screen. I was using the computer and I think I have right clicked the mouse, the icons became very large and when I tried to make them smaller they became too small and the screen "shrunk" the Taskbar has also got larger..
I am in need of some advice as I am not really computer educated as yet and get confused with what I am supposed to do
I would be grateful for some help
Thank you

 

You probably changed the screen resolution by accident.

To change it back, click on the Start button then on Control Panel. Click on Appearance and Themes, then click on Display. Click on the Settings tab.

On the lower left of that window there is a slider. Using the left mouse button, slide it back to 800 X 600. Click OK. See if that changes things back to the way you want them.

If the task bar is still too big, hover the mouse cursor over the top edge of it until the cursor turns into a double-headed arrow. When it does, press and hold down the left mouse button and drag the task bar back down to the size you want, then let go of the button.

 

Thank you so much for your advice Miz. I tried what you said and changed the screen to 800 x 600 but the the icons became huge. I don't know what I originally did to change the screen appearance as I didn't go into anywhere to change anything.