I red your other thread that you link. I would be in the same place as you Scared There not much that we can do because of school IT department but I would definitively go to your Student help desk department and talk to a school technician and see what they can do to help you.
How are you connected in a dorm room?
Does the Access Point require a password?
Here are my suggestions
I would recommend Spy Blaster. What this program does prevention of any spyware from corrupting your HOSTS file. it locks down your HOST File so any spyware or malware rewrite your Host file will be block. This program isn't a scanner. http://www.javacoolsoftware.com/spywareblaster.html
Make sure you set the computer to not Logon automatically. Set s Complex Password to your computer. This acts as a complex password $P@ssW0rd!. Always Lock yout computer Windows Key +L when you leave. You can buy a External Hard Drive and copy all the stuff that is personal related and you can know you stuff is secured and with you.
You may want to bring that link with you and talk to a technician with that at hand if your wanting to do that.
I hope that helps you out