Ok, I have found a solution to either Disable or Uninstall. You cannot change any Options or Passwords. Close Firefox, Hold SHIFT and Double-click Mozilla Firefox from your desktop. A dialog box will pop up. Do NOT select any check boxes. At the bottom click on Start in Safe Mode. A small Firefox window will open. Do not enlarge. Go to Tools > Addons then it will allow you to select either Disable or Remove. I hope this helps with everyone's problem. Please leave comments so I can further assist if needed.