Now, when I click "System Properties", nothing happens; no window pops up.
You ran System file checker earlier (my instruction at post # 10) now that's been done try right clicking on " Computer" and choose "Properties".
Can you get to "Advanced system settings" now?
Google Chrome begins to act slow with only four tabs open (pages will freeze)
Try resetting Chrome and see if that makes a difference.
Go to the link below and follow the instructions on how to reset Google Chrome browser settings:
When I try to go CTRL+ALT+DEL to see which processes are hogging up memory
Right click on the task bar and click on Start task manager. Check out the tabs to find the information you want.
When I click my HP Support Assistant (it says important action is needed), the PC looks like it's thinking, but won't open it.
Maybe your HP Support Assistant needs updating.
The latest installer for HP Support Assistant can be downloaded from the page on the link below.
Try the foregoing actions and tell me if they make a difference.