You should try to run “Pimp my Wii”: http://www.wii-info.fr/download-450-pimp-my-wii-1-40.htm
I have an external HD partitioned half NTFS – half WBFS.
When I plug the HD: – All the videos on HD crash – All the videos on SMB crash (?)
When I unplug the HD: – All the videos on SMB are playing OK