Only thing I could think of that might have something to do with it is the visual tweaks, but none of them aim at icons.
It is easy to enable those, you can do with with the program, or do it in Windows itself.
Go to the start menu and right click on Computer and then click properties. When it opens click on advanced system settings on the left side.
When that opens click the settings button under performance at the top. And here is where you can put the visual settings back, you can set it to best appearance and hit apply and then reboot and see if that helps
Shane