so "Authentication - JFBConnect Social Integration " yes or no?

It's required for authentication in general. I'm not sure how users would be logged into the site if that's not enabled. It also handles some corner case issues, like if you deleted a user from Joomla's database without removing the entry from the JFBConnect UserMap table. There's also some logic with the socailprofile plugins to check extended approval information for some systems that allow more granular blocking access for user authentication.

In short, leave it enabled or things may not work as expected.

Thanks,
Alex