bit of a newb to running my own server. bare with me please

I set up a Mac Mini to act as a web site...very small web site...only a few people will be view it...however, I just want to make sure it is secured.

What are some crucial settings that need to be set to ensure there are no intruders?

Also on a mac, I have a domain pointing to my IP, which displays files inside the HD > Library > WebServer > Documents

Inside Documents, I have phpMyAdmin...which is totally insecure and open to the world. Should I just remove the folder and only put it in when I need it? or is there a more secure place I can permanently put it? What about password protection?

Thank you!

change the folder name is the simplest step of all

the script kiddie crackers only search for common names when looking for security holes.