Before going so far as to reinstalling X-Plane, I would recommend you to delete your preferences (which in X-Plane 10 are in a folder called "preferences" in the " Output " ) after duplicating the "preferences" folder. It might cure some malfunctions … you will to redo all the calibration and assignation of keys and buttons if you use a multi buttons joystick. It can take time, but much less then reinstalling.
Reinstalling can be tedious especially if you have a larger library of pay-ware aircrafts, sceneries and add-ons . You should always make a full backup of your current X-Plane folder on a separate hard-disk before going so far as to reinstall the full X-Plane.
A medium solution would be to update your X-Plane to the latest stable version, and carefully look at the last additions or modifications you made to your current X-Plane set-up.
Have you installed a new plugin or new aircraft or add-on that installed a plugin that does not behave well?