How to enable user registration, but don't allow any of those users to login? I want to use the user registration page to collect user data and use its email verification checking to filter out fake users. But the thing is I don't want these users to be able to login to the site. How can this be done in Drupal 7?

Note: So no login at all. I just want to use the registration system to send them an email to verify their account.
You could use Rules

Event: After saving a new account

Action: Block a user >> data selector: account