Reformatting PC

Few months ago, my old desktop already showed signs of slowing down. I'm guessing that is due to too much programs installed and probably due to nasty virus. Most of the times my niece or nephew sneaked in using my desktop and I believe they might have infected my computer. I have tried to speed up my computer by removing some old and not in use files so it can breathe a little but it's just the same.

I was forced on having it reformatted by my technician because it’s not improving and I needed my pc in it’s original faster shape. Thankfully, it’s back to normal now.