Computer Help and Support

get a 'non-responsive' message and my mouse won't let me click on anything. I'll reboot the computer and the same thing happens the next time I open my browser and any program. I reset defaults. I ran chkdsk. Defrag is on automatic and a message came up that a defrag was unnecessary. I cleaned out temp files, cache, trash bin, etc and it still is happening. Then I went to my anti-virus program and when I opened it - I got the same non-responsive message. After a long time it finally became responsive and now I'm running a computer optimization task. It is a laptop computer. It's running slow as well. This message I'm writing here is being sent from my iTouch. I thought it might be a problem with my internet provider - but my iTouch & Samsung S7 are able to access the internet - thru my wifi - and are functioning fine.
I have a lot of work to accomplish on my laptop and this non-responsive thing has held me back. Any suggestions will be appreciated. NOTE: This whole thing started about 4 days ago.