My Windows recently starting minimizing, expanding, and closing windows at random. I'll be working on a PowerPoint, for instance, and the window will unexpectedly minimize, pop back up, or scroll. Eventually it closes on me. Then if I try to click on the Start button, it flashes the menu up for a second, shuts it, might pop it up again briefly, or it might stay up long enough for me to turn off the machine.
I have done a Windows repair re-load and it still does it.