because your datughter's account may have a program ending and you just switched users, but did not log off, so it's still running.
I never had a problem shutting down Windows (XP SP2)until I created an Administrator password for myself and gave my daughter User access to my computer. Now whenever I try to shut down the computer for the night, I get message after message saying that one program or another is not responding, and I have to choose to "Return to Windows" or "End Now." It's usually the same programs that are not responding. Naturally, this takes a whole lot of time and, after enduring this for months, it's very frustrating. Any ideas why this is happening, or how I can remedy it? I've cleaned the disk and defragged the computer.