Computer Slowdown

PC: Dell Dimension 1100 Desktop
PROCESSOR: Intel Celeron D - 2.53 GHz, 512 MB RAM

Here's my problem: I'm not sure what could be causing it, but it seems that, after running for a few hours, maybe 3 or 4, performance begins to slow down, and, according to Windows Task Manager, CPU Usage is at 100%, and I can't discern why. I've been running the same programs that I always have, two constantly - EMule Plus & eLePHANT (Both P2P Programs) - and have never had this problem until about 2 days ago. I've scanned for spyware, viruses, and whatnot - I have NOD32 Antivirus, and SpySweeper & WinPatrol as my antispyware, and all three also help detect Trojans, Worms, and other threats - and so far, nothing that would have caused this problem. Well, it wouldn't be a problem if, every time this slowdown occurs, I have to restart my system. Again, I haven't been doing anything different than I have in the past with this computer - Listening to music, obviously surfing the internet, watching video clips and DVDs, and downloading with EMule Plus and eLePHANT. I've also cut down on the projects I have going all at the same time, usually leaving my P2P's off while I surf the internet, etc., and no matter what I've tried, the slowdown still occurs. Any help anyone out there can give me will be GREATLY appreciated.

 

What firewall are you using? I don't use P2P, but the kids do. We use a commercial Internet Security Suite.

 

Have you done a cleanup lately ?
Try emptying the swap file/virtual memory, -
Right click My Computer, properties,advanced,performance settings, advanced, click first two program spots, to use less for cache, more for programs, and -virtual memory,clickchange, click no paging file, click o.k.
Shut down restart, go back to virtual memory, and change to one and a half times the ram you have installed.
In internet options, click delete cookies, delete files, clear history, click apply, close .
Restart Explorer to clear.

 

Check your Firewall permissions, and edit the rules to disallow anything except microsoft, and antivirus from getting to the web.
You can allow it when asked, if you know what it is.

 

1st I would removing Norton and installing Avast.
If that that works great. If not install ProcessExplorer http://www.majorgeeks.com/Process_Explorer_d4566.html
and then looks to see what is using up the CPU.
With the ProcessExplorer you can kill the process that is hogging up the CPU.
If this is the case, let me know and I will try to help you in removing this from bootup.

 

Okay, first, ROSSS, I'm not using Norton; I'd kill myself before I ever did that. My antivirus program is NOD32, created by ESet, and it does a really good job.
Anyway, here's the answers to all of your inquiries:
First, I just simply use the Windows firewall, and I do allow only things from Microsoft, my P2Ps, my antivirus and antispyware programs to come through automatically. Otherwise, I occasionally let some things through manually, if it pertains to something I have installed. Even if something does go through the firewall without permission, my WinPatrol and SpySweeper will about 99% of the time pick it up and alert me. That's why I run a full, deep system sweep with both SpySweeper and NOD32 at least once a week, and everything they have found lately has been trivial stuff, and easily deleted.
Now, as for cleaning up: I probably should've mentioned in my first post that I have two hard drives installed; both are 80 gigs each, and I use the slave drive strictly for storage, not running any apps or other programs from it. I do that from the master drive. Also, neither are anywhere near to capacity, so space definitely isn't the issue. Plus, I clean both out usually every two days, using a combination of the Windows utility from Control Panel, IOBIT's WindowsCare V2 Personal (Freeware Edition), and Privacy Mantra, which basically is the "cleanup batter" I use after the first two programs, since it can catch some things the other two programs don't. I never run all three at the same time, nor has there ever been a problem before with any of these programs clashing, or anything like that.
Even after all of that, I'm still having the same problem, and help is still greatly appreciated.

 

Ok. Did you or did you not run ProcessExplorer?

 

Well, I did download it, and with it, I actually found nothing that would be causing that problem. The funny thing now is, the problem has somehow stopped on it's own, as of about an hour ago. As far as I could tell, it was nothing I did to it; It just decided to stop running at 100%. I have no idea why my computer wants to screw with me, but I'm gonna keep hoping for the best, and hope it isn't the start of some bigger problem, or anything.

 

This may be irrelevant, but I have had some severe slowdown problems due to the Indexing Service - there are three components, easily recognized, and in my case I was running iTunes, which updates an XML file for each track ripped from a CD. The indexing service goes chasing its tail, trying to keep the index database up-dated. First I stopped the service, then stopped it indexing XML files, which cured the problem. If this was affecting you, you would see the indexing components in Task Manager.

Even if this is NOT your problem, it is one you may choose to put into your memory banks against a rainy day...