Omg! Windows 10 Trashed My 'puter! Help Please!!

Hubby has a Dell OptiPlex 9030 AIO that was running Windows 7 Pro. He has only been using a computer for a few months and has a lot to learn. He decided to install the free Windows 10 without asking me first. Now I can't do anything with it. I do get the Windows screen when I turn it on, but nothing from there. After some time I am able to pull up the start menu, then I click on Control Panel. Some 30 minutes or so later I get a box titled "Microsoft Windows". It states: This application is not responding. The program may respond again if you wait. Do you want to end this process? If I wait it simply goes to a black screen.

Is there any solution or should I throw the 'puter in our pond?

 

Thanks for your quick reply, plodr. I tried the above. Pressing F8 did not work. However...since writing this first post I decided to unplug the computer, wait 30 seconds then plug it back in. That seems to have helped for the moment. I was able to get into the control panel. I chose System Properties > System Restore. I chose a system restore and it ran a scan for programs and drivers that might not work correctly after the restore. The only one on the list that concerns me is "Intel (Net) 9/28/2014...Type: Driver". What's your advice?

 

Sorry, plodr...but all that might as well be written in an alien language. I should have mentioned that I'm not very computer literate when it comes to the "techy" stuff. So, should I do the restore? If I do, can I download that driver?