Ok, two things going on in your PC:
1.- Your CPU is reaching up to 91ºC causing some throttle down here and there (though not as much as I would have expected with that temp), these throttle downs hinder your PC performance. Make sure to deal with this ASAP, clean out all the dust inside your case and fans, and it seems its time to apply fresh thermal paste on your CPU (lots of youtube guides for this).
2.- Your HDD usage is at 100% during the whole test, even before you launched whichever game you've used, so take a look in your task manager to find out which program/process is using so badly your HDD. Having it at 100% usage often slows down heavily your system. Btw in those almos 20min of test your HDD read over 13GBs of data, something's clearly wrong there.
As for your PSU, it seems to be holding up just fine, so for the moment you don't need to worry about it, but it's highly suggested to replace it with a quality unit when your money allows it. A 500w model like the XFX TS or a Seasonic 520 S12II are far better than the 750w you currently have.