Also, how can someone outside your router get through its firewall and into your shared folder? Wouldn't the firewall ignore such an external request?
I don't know the specifics. I just know that when you enable NetBIOS it allows someone else to add your computer's public IP Address as a mapped hard-drive. They can then use any explorer.exe window, type in your IP address and get into your shared files. On a 2000 your hard drives are shared by default, so you would gain access to the entire computer. Thankfully on a 2000 if you require users to enter a password before logging on the same is required when attempting to access shared files.
