TW launcher is TouchWiz, the default Samsung launcher. Something may be corrupt in your settings. You can try a couple of things. First got to the play store on a PC and try and push an alternate launcher to your device like Nova or Apex. If it installs, then you will get an option to use TW or the new one, chose the new one, but only once, not always. Then open settings>apps and find TWlauncher and clear the cache and data (that will also clear your home screen settings so you'll have to set it up again) then try and use TouchWiz by pressing the home key and selecting TWlauncher. See if that works for you.