After installing this week's Windows Updates, I notice that the GIF and JPG icons on my computer have changed ... and when I try to go into "Folder Options" and change them back, the change doesn't take.
Thanks for the suggestions. I've done all the things you've suggested, Guru, to no avail. I'm gonna take it up to my girlfriend's house tomorrow and use her machine for testing purposes while she's at work. I'll let ya know how it turns out.