Computer Using Ram And Cpu But Can't Find What Program Is Doing It

The issue here is all my programs would freeze and I was like wth is going on? So after it happened a couple of times, I finally figured out what was going on. The system was using cpu power ranging from 20 to 50 percent and my ram was using roughly 20 to 32 percent. The weird thing about this is my computer cpu usually is around 2-5 percent and ram is around 5-12 percent when doing normal day activities.I have a vortex 120 gb and I have it updated to the latest software. My hypothesis is that there is a system defragging working in the background because I see my hard drive space going up and down. It'll go down 20gb and go back up. Sometimes goes down a lot sometimes not that much.I have three programs and I've tried closing all three.

Bitdefender-no auto defrag Iobit advance system care- I turned auto defrag off but even it the settings it's already checkmark not to defrag ssd tuneuputilites- turned off auto defrag also and same thing as earlier, there's already a checkmark to not defrag ssd
edit(forgot to mention that I turned system auto defrag off also)I ran antivirus scan and malware scan already with no luck.So here's where the big mystery comes into play. Even though there is cpu usage and ram usage when I go to windows task manager, I can't find anything that shows it's using ram and cpu even though it is.Very annoying with everything freezing. Even if I restart it still continues.

Computer specs
-nvidia special edition case
-i7 975 extreme edition
-16gb ram 1600mhz
-120 ssd
-1.5 tb harddrive and 1.0 tb harddrive
-sapphire 6990 graphics card
-5fans
-windows 7 64bit ultimate edition