I shut off everything via CTRL+ALT +DEL (except explorer) and I am still using 20% of sytem resources according to the performance tab in "SYSTEM Properties". What could be running ?

Windows 98SE
511 Ram
Dell 1.8g processorSo,first of all your computer is clean and not overheating
correct?Clean and coolHave you ran an anti-virus program?Yes I have AVG. I ran a full scan. I also ran: CCleaner, Ad-aware, Norton Win doctor(ran utility from CD), I ran scandisc (thorough) and then I shut off everything via CTRL+ALT +DEL (except explorer) and I am still using 20% of sytem resources according to the performance tab in "System Properties". Try Security Task Manager--->Here

You get a 30 day free trial.System resources in 98se indicates something entirely different from CPU usage. There will ALWAYS be some resources in use, even after a reboot. This is perfectly normal and is not anything to worry about unless the system runs out of system or gdi resources. Unlike newer versions of Windows, in 98/98se these resources are limited. There are many things that affect resources. Items loading at startup, even if you end the program, will leave portions in memory so they don't have to be reloaded. .dll files often remain in memory for some period of time after the program is closed. Thats the way Win98 operates. I hear what your saying, but this is recent. My computer SLOWED down when this happened and I compared it to my other computer that has the same programms and operating system and it has much more resources available. When everything is running I'm using over 50% of my resources before I do anything. When my operations got slow and CHOPPY it prompted me to start looking for the problem.  Is there a way to see cpu usage?Yes. If you have your win98 system tools installed you can check lots of things. System Monitor should appear under accessories/system tools. If it isn't there, you will need your windows CD to install it. After you open system monitor, click the edit tab, click add item, click kernel, click kernel usuage. You can select the way it is displayed. LINE, bar chart, and number are the choices. Choose number.