All pics saved as "hidden"

Is that what the little "padlock" on the icon means?
I have Win Explorer set to "show hidden files" and have unchecked the "hidden" button on each file's properties, but Explorer still won't show them...
I can only see them through a 3rd party app, IrfanView
Any ideas?

The padlock indicates that access is controlled or limited. Your user account (as well as other users accounts on that computer) are limited access by default. It's primary purpose is to limit access by other users to your data and visa versa but it can be altered via File Permissions. Can you see the photos under Libraries ... Pictures ... My Pictures?

It could also be another issue. By any chance do you use McAfee Antivirus? There was a problem a little while ago where McAfee's AV was setting all photos to hidden and I do not know if that has been fixed. Check out this thread HERE. If you are using McAfee then you may want to do my suggestions for running ATTRIB to restore your photos (of course substitute your userid where I specified redstar79 for that user.

Note: Apparently if this is a McAfee issue then the files will get re-hidden every time the AV runs it's scans.