System Process using 100% CPU

//Edit: Issue Resolved, so if you were here to help, thanks, but you don’t need to waste your time reading my big long story =)

I’m having problems with my Dell Dimension 4550, 2.4 Ghz P4 w/ 1024 mb RAM.

Short Version:
The “System” Process is taking up 100% of my CPU power and I can’t get it to stop. I’ve tried AdAware and Spybot and now I’m scanning for viruses.

Long Version:
I woke up this morning at five o’clock to a clicking sound. I didn’t think much of it because my Linux box sometimes runs through something like this in the morning, not sure what it does, but it usually lasts for about a half hour and shuts off, I suspect it’s something cleaning out the system or something which is why it can go for hundreds of days without a reboot.

Anyway, I went back to sleep and woke up again two hours later (my alarm went off) and the clicking was still going on. I walked over to see what it was, and it was actually my External Hard Drive connected to my Dell that was doing it. Now this is odd, because that is usually just used for storage, so I don’t know why it would have been spinning.

So, I powered on my monitors to see what was up. Samurize showed that my computer was using 100% CPU and was recieving files at 600 kbps and sending at 400 kbps. This was extremely odd because there were no programs except AIM and MSN Messenger that I had left open over night. And there would be no reason for this. I couldn’t get it to stop sending and receiving stuff or to stop using all the CPU, and since I had to go to school, I tried to shut it down, hoping to be able to fix it when I got back.

It hung up on shutdown, which is also very weird, it has never done that to me before. So I shut it down via the power button.

I got back from school and booted it up. This took a lot longer than usual also. It took about 10 minutes or so to boot up and when it did it was still using 100% CPU via the “System” process. And it also failed to start up Samurize which is set to startup with the computer. Well, not really failed to start it up, Samurize started, it just didn’t appear on the desktop, only in the task bar.

So, I tried to get this to stop but to no avail. I tried running Spybot and Adaware, and am now running a virus scan. Spybot found nothing, AdAware found a few tracking cookies, and the Virus Scan hasn’t found anything yet.

As I was writing this (on my laptop) the CPU usage has dropped to about 50% but it’s still unerving (sp).

I haven’t installed any new software or hardware recently and I have no idea what could have triggered this. I have also disabled a bunch of programs that were starting at startup in hopes of getting rid of any possible interferences. That didn’t help either.
End Story

Thanks for taking the time to help me =)