How to make an advanced server-based database ?

Hi all of you out there,
well...hmmmmm...
I wanted to know how to make an advanced server-based database. I mean, I'm a simple 17 years old student programmer, and dont have heavy basis for hiring programmers.
The "server" I currently have is my own PC, which has a static IP address.
I want to develop a comunication program, which will be Users-Based, and each user will get his own access-level to the system, individual statistics on each user, etc.
I already have the database structure detailed.
I just need to know how to put it on a server and to use it effectivly.
For now, I just have the option for running an FTP-Server program, and letting the users to logon the program system through the FTP. but it kinda looks lame. It is also VERY vulnerable for hacking attacks.
Oh...and it's very complicated to manage this kind of database when it's located on an FTP.
because with FTP, I get access only for files, and for getting very detailed info about a particular part, it is getting almost impossible.

Well, In short, How can I manage a database based on a server with the current equipment I do have, an equipment every PC user has. ?

Thanks.