Correcting Shadows

When "normal" or "Extra" Visual Effects are turned on, the shadow from the top toolbar is over windows.

To check this, right click on the desktop and go to Change Desktop Background. From here click on the last tab "Visual Effects"
Normal or Extra will probably be ticked, if not you should tick it Normal as it makes things a bit easier on the eyes.

To fix it:
System > Preferences > CompizConfig Settings Manager
(If this is not visible it may either be hidden or not installed.)

In Compiz Config Settings Manager scroll down to Window Decoration (Under Effects)
Click on Window Decoration
Then copy and paste the following:
(any) & ! (class=Gnomre-panel)
into the "Shadaow windows" text entry box.

Ta DA, Windows are now a bit more legible.