Removing and reinstalling oziTarget is not likely to fix an issue. The settings and some support files will remain on the computer separate to the main oziTarget folder and will require the scorched earth approach described on the website above.
Deleting oziTarget or Oziexplorer and putting them back on again is seldom the fix you are looking for.
Installing a new version of oziTarget will write over the top of the old version and does not require removal of the old version first. Just make sure the old version is not running when you do the update. A reboot after install can't hurt either but should not be needed.