Yes, you can disable this user - Easydiscuss plugin but I am not encourage you to do that is because what this user plugin does is when the user get deleted on your site, it will convert all his user discussion/tag/categories/comment owner ID to your site Superadmin ID based on what you set it from your setting (http://take.ms/hCbTV).

It also will deleted all his previous conversation/likes/votes/subscription/badges/points/categoryModerator as well.

I originally asked this question because after converting to EasyDiscuss for forum a lot of users were having cookie problems where they could not stay logged in. I thought this had been resolved but apparently a lot of users are still having problems staying logged in. Is there a way to delete all of the cookies for my site for users, and have them login and form a new cookie?

Currently we do not have any ideas for this, but i believe Joomla store those user cookies in this table #__user_keys .