Hello,
You have a lot of problems, both with your configuration and also your understanding. I'd like to suggest you find a friend who has experience in managing these kinds of systems to help you.
If you remove the # from NSDefKill this will only affect NEW nickname registrations, not existing ones. Do you understand what this means?
If this is a screenshot from your configuration file you seem to be missing lots of the useful help information, I would recommend strongly you base your configuration on a standard example.conf which includes lots of useful help.