BuddyPress.org

@blackmatarsak,

Ans 1, you can hide it with simple css in your theme by using :

#wp-admin-bar-wp-logo>.ab-item .ab-icon {display:none ! important}

I dont understand the question 2

Naijaping

@blackmatarsak,

you can follow this article

http://wpmu.org/how-to-build-a-facebook-style-members-only-wordpress-buddypress-site/

@blackmatarsak,

1) of course, you paste the code after a php closing tag. You also pasted the very first line of the code  which is only my comment.

Remove the closing tag and comment the line with two // or remove it, and things will go better.

Aside, theme’s functions.php use only a php opening tag, never a closing tag ( ?> )

2) can be easily done. See on Codex, profile fields and how to create new profile fields. It’s made on dashboard > users >profile settings