NIS 2009 Smart firewall is not blocking!! help

Hi everyone.

I decided to be a part of this community, 'cause I think this is the only place that I will get an answer to my question.

First, I bought the Norton Internet Security 2009 because I trust Norton, it is the best.

But, since there is a online security check provided by symantec, I was so curious to see how my NIS was really working.

so...... I decided to give it a try and I did the check, and when the results came out with this:

 

1. Hacker Exposure Check 

Everything there is Stealh, so far so good.

 

2. Windows Vulnerability Check

Here there is no problem. So far so good too.

but....

 

3. Trojan Horse Check

There is an open port. 

I have a wireless router from Netgear (the wireless connection is block),

Now my question is just one, if I have the NIS 2009 and the smart firewall, why the online security check, is telling me that I have an open port which let  my computer and data vulnerable to Trojan horse attacks?

How can I fix this?

Any answer will be appreciated.