ummm, I really can't make heads or tails of what your trying to say, but from what information I was able to get from your post it sounds like maybe you have a trojan.

The way it works is they put a code into the computer and suddenly the computer is being operated off-line
Im not sure what you mean like this, but if it is a trojan, then someone could remotely shut down or disconnect your computer

]They completely took over my e-mail address
this could also be accomplished using a keylogging function available on many trojans

I would advise getting a cleaner or virus scanner if you dont have one already - you can get a good cleaner at http://www.moosoft.com

I may be able to give better advice to you than this but you will have to be more clear in your post what your problem is.....like I said, I can't really figure out what your trying to ask