Ahh, it sounds like your icon cache is not updated correctly. Restart the computer in safe mode, and then try to arrange the desktop icons.
You may need to uninstall Fences.
Alternatively, you could try the following steps:
1. Right-click the start button and select "System".
2. Go to Advanced System Properties.
3. Click Performance.
4. Change the setting you have now on visual to anything it isn't set to. Try toggling these once or twice and see if that fixes the issue for you.
Hope this helps!
-JP