Everyone here should know that you are not safe from hacking!
I have a firewall up and I have noticed many many port hack attempts at the kazaa ports I have used. I dont know if anyone else has written this here but windows recently admitted that (i believe) ALL of their OS's have a critical flaw in them which allow attackers to obtain virtual control of the computer.
Go to your windows update and install the critical updates ASAP if you haven't done it. I have found that I have had an amazingly smaller amount of port hack attempts since I installed the update.