Messages "this program is not responding"

Hello,

for a few days now, when I try to shut down my PC, a gray dialog box appears saying "this program is not responding" with a choice between "end now" or "cancel," and this is for two programs: HIDDEN SHUTDOWN MONITOR WINDOW and KPFA MAIN WINDOW.

I should mention that a few days ago, my PC was affected by a virus or spyware or something like that, which I removed using SMITFRAUDFIX, according to the always good advice from this forum.

But either the intruder wasn't completely eliminated, or I mistakenly deleted some files, I'm not sure, but since then I've been getting these messages every time I shut down.

Can anyone explain how to restore the situation to normal?

Thanks in advance

Configuration: Windows XP media center SP2