Right click your Task Bar and select Task Manager, then click the Performance tab. Look at your Memory Usage and CPU.
Leave Task Manager open and open something else. If your Ram or CPU is pegged out, or both, you might be able to add more Ram and get by.
Programs load into ram first then when none is available they use your your page file or virtual memory on your hard drive.
This makes your CPU work harder.
You can get Ram pretty cheap for older machines, I use Crucial
, they have a scan tool and stand behind what they sell.
Another thing you might look into is backing up your data and wiping your drive and reloading XP, clean start. Maybe get a new drive and use the old one for backup.
Edited by ratchet48, 06 February 2010 - 10:50 PM.