Well, I guess there is nothing left to be done, besides:1.
Clearing your computer from all junk files, unnecessary programs and everything which you don't need. You can disable, for example, the animations on your computer so that it runs faster. You can use a program like CCleaner to clear your computer just with the clicking of one button.2.
Reinstalling your OS for a faster, more painless process of doing the same as in 1.3.
Installing a lighter OS, such as Linix Mint or Puppy Linux, which uses less resources.4.
Buying a new computer. Pretty much any machine with Intel Core i-series CPU, especially 4-core ones, 8GB of RAM, 1TB of SSD and Windows 10 Home OS, can run anything
in the world, apart from some games and graphics programs. This type of computer should be 'good' for another ~5 years.
But in your case I would suggest cleaning your computer both inside and out (software and hardware) and only opening up 1 program at a time. Also, avoid playing HD videos. Try using CCleaner for cleaning your PC relatively fast.
Finally, when some process is using a lot of CPU % in Task Manager, you can try to click on it with the right button and then setting its Priority to 'High' (but not 'Real time'!).
Hope this somewhat helps!
Edited by Just_One_Question, 31 March 2017 - 10:37 AM.