Intermittent lag problem

Have an intermittent lag problem with my computer. Been trying for three months to solve this to no avail. Here's what I got:

Every ten seconds or so, the computer freezes for a couple of seconds when I do something. I look in the task manager and when the freeze happens, the bar goes up to 100%, after that it goes back to the normal 2-20% range. typing, scrolling, and movie viewing are the three things that set it off more frequently. However, when absolutely nothing is happening with the computer and I just watch the task manager meter, it still blips up to 100% every 20 to 30 seconds.

I have done numerous virus scans with Mcaffee Viruscan pro, I have completely uninstalled and reinstalled Windows XP Home, I have tried shutting off various processes from the task manager to see if that could be the cause (most notably, the AOL Spyware protector and McAffee Viruscan). Yet the problem persists. I almost think I have some kind of hardware malfunction.

Here's the stats on my system:
Gateway PC Performa 3800
1.4GHZ Intel Pentium 4 processor.
512MB of physical RAM
Raedon 9700 video card
Windows XP home installed
From the performance tab of Task Manager: Commit Charge (k) total: 332596, limit: 5655036, Peak 417300 Physical memory (k) Total: 654640 Available 226984 System Cache 438556 Kernel Memory (k) Total 61984 Paged 40984 Nonpaged 2100 PF Usage: 324 MB

Please let me know what more information you may need. Those are all I know of to work on. Could use other suggestions to help solve this problem.

Thanks
Elie

 

AOL adds so much junk onto your PC it can slow down any PC and they are always prompting if you want more junk. It happens to my sister in-law all the time. If you really want to use AOL install only the bare essential when you install it and uncheck all the extras and decline when prompted.

To stop most of them Run MSCONFIG and select the Startup tab and uncheck almost everything except Micorsoft and your virus entry. You can recheck any of them if you find you needed one you unchecked.

The problem could also be spyware. There are many utilities available to detect and disable them. Ad-Aware is one I like, see: http://www.lavasoftusa.com/support/download/

 

Tried shutting some stuff down in MSConfig. Didn't fix the problem. But I'll keep trying that, maybe I'll hit on something I don't need. As for Spyware, I have SpySweeper on my computer. I put it on when I first started noticing the problem.

Thanks. Any other thoughts or suggestions, anyone?