computer unresponsive/freezing while 0% cpu and memory use

so on october 1st ive started getting problems with all programs becoming unresponsive or very slow (especially when starting/closing them). since then ive used malwarebytes , microsot sec. essentials and Ccleaner to try to find any malware but it didnt fix the problem. i tried system restore and the problem stayed around. ive then tried to use 3 different microsoft fix-it tools (performance, maintenance and files). then i used disk cleanup and removed about 7gb of old windows update files and that has seemed to help a little, but i still get more hangtime on programs than before.
programs relating to the internet seem to be especially prone to this, as skype and geforce experiance update seem to become completely unresponsive.

tried it and the issue is just as bad in safe mode.in fact it appears even worse, like before i did the disk cleanup in normal windows.

i used the western digital data lifeguard diagnostics tool and when i try to test the drives it reports and error when testing

the test only fails when i try to test drive C: , can you suggest some ways to check/test my drive for bad files or sectors?

/scannow went through with a 100% integrity. but today after booting up the computer i noticed that microsoft security essentials have been deleted