Um, Windows Update doesn't download and install anything unless you let it.
Well I guess that's true, if you include enabling automatic updates as letting it. I don't get to pick and choose or even get prior notice of specific updates. By the time I hear about it, they've already been downloaded and installed, and Windows wants to reboot to install them.
I guess it's no hardship with the amount of time I use IE, but that backspace "bug" is really annoying.