Account Activation - User Activation requires the new user to activate their account by clicking a link sent to their e-mail address. Admin Activation requires an admin to activate the account using the control panel or by a link sent to their e-mail address.

Limit Username Characters - Limit the characters allowed in new username registrations.

Username Length - Minimum and maximum username length.

Password Length - Minimum and maximum password length.

Send Welcome E-mail - Whether or not to send a welcome e-mail to all new users upon registration.

Enable Captcha - Do I want this?.

Username Lowercase - When set to yes, all registered usernames are made lowercase.