You might want to give Undead Pixel a try; even if it doesn't work, it has a cool name. It will not work every time, but it essentially quickly cycles the pixel, which can sometimes "unstick" them. Undead Pixel is freeware, so you have nothing to lose, and if it works you can always donate a buck or two to the developer.
Another thing you can do is apply direct physical pressure to the stuck pixel, in other words press it gently with your fingertip. Believe it or not, sometimes this is all it take to fix it.
Answer
You might want to give Undead Pixel a try; even if it doesn't work, it has a cool name. It will not work every time, but it essentially quickly cycles the pixel, which can sometimes "unstick" them. Undead Pixel is freeware, so you have nothing to lose, and if it works you can always donate a buck or two to the developer.
http://udpix.free.fr/index.php?p=dl
Another thing you can do is apply direct physical pressure to the stuck pixel, in other words press it gently with your fingertip. Believe it or not, sometimes this is all it take to fix it.