Hey! You just trying to make me feel good? I did the same thing a little while back and still feel pretty stupid; same results (the update was and IE8or9 update). Finally had to pull out my restore disk and start from scratch; ie reinstall Windows and all the drivers, applications etc.
If someone else knows a different way, jump right in here; but that was my experience and probably what you will have to do.
At least you can point to innocence cause kids don't know any better, I did it to myself.
6/6/13, 2115 hrs. PDT I may have jumped ahead of myself here. Sorry. When you reboot do you get the boot screen?
My thought is that if you can hit F8 just when Windows would boot you might be able to boot into 'safe' mode: From there you could go to system restore and restore back to before the update. I hope this works, good luck.