If you want to completely get rid of Spybot-S&D 1.4 (also earlier versions) and the Add/Remove doesn't help, you can delete the installation folder (usually C:\Program Files\Spybot - Search & Destroy\), then download this very small fix and execute it (important! - this will remove all remains from the registry) (this also applies to earlier versions).
If you just want to upgrade to a newer version, please follow the same instructions like above and then install the new version.
After following these instructions please restart your system so that the changes can take place.