Help need to know if malware was attacking my computer

i recently connected to my schools insecure wireless network that they let the students use and the second i connected the firewall event logs were going crazy. in a couple of minutes it hit from 25 intrusion attempts blocked to 42 and i did not even go to any site. a minute later i went to my homepage and my schools website. the destination ports were 9100, 161, and 137. now i know other people were connected to that wireless network but is it possible someone was trying to hack in even though it started happening within two minutes and i only went to two good reputable sites. also under application it said system and windows operating system. i am using windows vista home premium 32 bit with the latest comodo firewall pro installed.

Now… I know computers will “chat” to eachother… and usually i think it is safe unless… Now i may be wrong about this but… If a computer is infected with whatever nasties there are now and those viruses/malware/spyware/etc is trying to connect to you from the computer it is on i know that is dangerous. But i freeload off the person next door and they have an open wifi connection and my CFP alerts me about once every hour about the other computers on the networking trying to access or connect to me. What i do is always click “Block this application”