It sounds like its messed up you profile. If you look in your profile folder, this site will give its location click here and have a search for bookmarks.html and save it to another location. Then delete the profile folder and restart Firefox, it will ask you to create a new profile. You will have to re-install all your extensions again, including Spellbound, because you don't know which extension its corrupted. You can re-import the bookmarks in the Bookmarks manager.