What you really need is a big ol' sledgehammer!
Sorry I can't offer much help, I'm not great with computers either but I think some of the previous answers may have been spot on with the Windows automatic update. One of our computers at work was doing that for awhile, then it stopped (probably someone who actually knew what they were doing turned that option off somehow).
I'm a Mac user for personal stuff so I don't have that problem with my laptop, though all of my Microsoft Office programs seem to want to update on the daily and tend to interrupt the incredibly "important" things that I might be doing at any given time haha.
All computers have their quirks, though, so I'm certainly not here to say one or the other is better!