Yes, the question sounds like I am a paranoid person, but seriously...
I have a machine that runs Windows 7, and I do not intend to update it. However, any number of programs have been acting oddly of late and the computer has been running far slower than in the past.
As an example, I just created an Excel spreadsheet and the contents were a) limited to a total of about three dozen cells and b) there was absolutely nothing fancy in the spreadsheet. I typed ctrl-s to save the file, and was greeted with an hour glass. After waiting a full minute, I clicked on the spreadsheet and the file greyed out, i.e., the program crashed or hung. Needless to say, upon restarting all of my inputs were lost.
So, is it possible that the updates coming from MS, such as those for MS Office, have been causing these problems? If not, I cannot imagine why a system that has been working fine for years is now acting so weirdly...