Thanks for your response. ...Sorry for the delay in getting back to you.
My problem was a "crashing" PC. While I had updated antivirus protection installed, malware was suggested as a possible cause, and it was also suggested that it might be best to run a scan using an antivirus program burned to a bootable disc. However, the crashing PC and a MacBook were the only computers available to me. Hence, the question I posted here.
I received several suggestions that my crashing PC might be due to a failing PSU.
After a lot of time and thought, I decided to take the plunge and buy a new power supply so that I could verify whether or not my original one was faulty. After I put in the new power supply, my computer stopped crashing and everything has been running smoothly. So...it was a faulty power supply that was causing the problems. (Therefore, I no longer need to use a MacBook to burn a disk that would boot a PC.)
Thanks, again, for your response.