I don't rant too often because over all I am satisfied with Windows/Microsoft; having said that, here is something that continually pisses me off.
I am a programmer/IT person, as such, I use the spacebar and enter keys on my keyboard quite often. I also like watching Channel9 videos. What I do not like is downloading the videos while I am working on my computer only to have it finish while I am typing. As many of you probably know the file will be move from it's temporary directory to the directory I have saved... Well, in the window that pops up (over the one I am working on, but that is another rant) there is a CANCEL button, yes folks, a CANCEL button. Not only that, but a CANCEL button that has focus. So as you might assume, pressing the Spacebar or Enter keys on your keyboard will, you guessed it, cancel the move operation forcing you to re-download your file... that's right, the 100MB to 800MB file you were downloading will have to be re-downloaded.
Well, that is not so much of a rant as it is a complaint, either way it is an annoying problem. Anoying enough I have even resorted to using <gasp>Download Accellerator</gasp>
Note: As I was typing this, I cancelled another Channel9 movie download... the same damn download I had to restart because I cancelled it 5 minutes ago...