[thelist] mysql security

[Joxn]

Hi,
I have a few questions about mySQL security:

1.) A port scan showed me that the mySQL server is open and running at 
port 3306. Where can I disable this?

2.) show databases; shows me a 'test' db that I can't drop claiming it 
wouldn't exist. Is this a mySQL DB that is necessary?

3.) The table DB from the DB mysql shows extensive rights to the test DB 
which scares me a bit. Simply delete or are these mySQL specific?

Are there any other tips you have?

TIA,
bye Joxn