Comment author must fill out name and e-mail

Check this box as a way to force spammers to do a bit of extra work. In reality, the name and e-mail address are not verified in any way prior to the comment being submitted. Most legitimate commenters are more than willing to fill out a name and e-mail address. However this option overwritten by wpDiscuz similar options in Comment Form Builder (Dashboard > Comments > Forms) :

The Name and Email fields can be set not-required using according option. However this options don’t hind these fields, they only make those non-required allowing commenters leave those empty.

Users must be registered and logged in to comment

If this checkbox is checked, only logged in registered users will be able to write comments on your site. However this option is also overwritten by wpDiscuz Comment Form Settings.

Automatically close comments on articles older than [X] days

Check the box and enter the number of days (e.g. 14 days) after which WordPress will automatically flag eligible posts so that no more comments are accepted.

Enable threaded (nested) comments [X] levels deep

Check this box to enable threaded comments, then from the drop-down box, select the number of levels deep (maximum of 10 levels) you will allow for nested comments. Note that themes need to be specially coded to properly display threaded comments.

Break comments into pages with [X] top level comments per page the [last/first] page displayed by default.

Check this box to cause comments to display in a paginated format with the specified number of comments per page. This will show the default [1][2]..[>] comment pagination buttons. I you want to change those to wpDiscuz AJAX [Load More Comments] button you should keep this option unchecked. More information in Comment List Settings.