Well, the first thing you should do is make sure your firewall is setup properly. Then, you need to do some penetrartion testing. Since you are asking for help, I will assume that ports, and firewalling ports, may not be your strong point.

Fortunately, people have setup websites, which will do penetration testing for you, to test the security of your machine, with some of the tools that crackers might use.

I am not familiar with your firewall, since I use Linux, and Mac OS X, and sometime Windows XP. Follow the instructions from your firewall manufacturer, and then you need to test things out, to make sure it is working properly.

I use http://www.dslreports.com/secureme

Folow the instructions, and create a login, so a detailed report will be emailed to you. It may take a while depending how many people are in the queue, but you must leave your computer connected to the Internet, until you get the report.