Can you show us a screen shot? Derek is showing tool presets in the options bar. If you are definitely seeing multiple identical icons in the toolbar flyout, then I'd say that something is broken.
With weird display issues I would look at the video card driver. It has to be updated from the card makers website.
If you still have an issue and a tool reset does not fix it, then try Preference reset.
If you still have the issue, then click on the three dots and then on Edit Toolbar, and Restore Defaults.
If still in trouble at this point, then a letter to the United Nations, and/or the Commission for Human Rights.
Thank you all for trying to solve this issue. However I stumbled upon the answer accidentally. I recently reset my screen display to show larger text as I was a bit challenged visually. When I reset it to the previous setting (this is on Windows 7) the problem magically disappeared. This confirms the old saying
When in doubt, do nowt..!
IfI had done nowt in the first place the problem wouldn't have arisen- just a pity I cant read the words on the screen so easily!