You may have noticed something new when selecting colors with the eyedropper tool in Photoshop CS5. It’s called the color sampling ring, and it shows you the previously chosen color, as well as the one you’re clicking on in a ring around your cursor. This can be particularly useful if you’re trying to compare colors.
However, if you simply don’t like the screen clutter you can turn it off. Just select the eyedropper tool and take a look up in the Control Panel at the top of the screen. You’ll see a checkbox for “Show Sampling Ring” which you can uncheck to make it go away forever.