...I don't understand what exactly is being asked for here.
I get that you want the computer to run 24/7, but the internet connection to be closed at certain times. What I'm not understanding is the utter insanity and paranoia that's on display.
You've stated that basically any way to connect to the internet has been closed, so what in Hades are you connecting to the internet for? Not having any MS components, flash, or scripts basically means that you can't do anything media related. Assuming that all you want to do is send conversations back and forth, why do you need the internet? There are dozens of ways to send simple text communications that are more secure. You're obviously not a completely paranoid person, given that you're asking for advice on the internet.
All of this said, what is wrong with the OP? If you want true security, you need to disconnect from the internet. If you want security through obscurity, run back track Linux. If you want security through a lack of features run a Mac. Trying to make a Windows distribution secure yourself is foolish. You cut off a dozen potential vectors for attacks, and you've officially lost most of your functionality. If you believe that MS, Intel, and your ISP is watching you then you've either got a reason to be watched or you've got some paranoia.
My only logical conjecture is that you're running something that may be fishy. A file sharing network, rogue peer to peer network, or any one of a dozen other things that you don't want to run during peak traffic hours (when ISPs heavily scrutinize high traffic users). If that's the case, please find some other place to pedal your questions. This forum doesn't harbor or tolerate activities that are either illegal or morally grey. If that wasn't your goal, then you've begun this discussion with a seriously skewed perspective. I can't help but think there is a language barrier here, because I don't see any other way to interpret this request.
