No solution yet. I'm completely baffled. I don't know another place to ask either. :-(

These were pictures I had saved from emails. They were not preloaded.

I've tried both methods you suggested. The pictures do no show up in the 'camera roll' folder, nor do they show up through my pc connection. I have no idea how this happened....

I have several pictures that I'd like to delete off my iPhone 4, but the delete symbol (the trash can in the bottom right corner), does not appear. I have the option to edit the pictures (which I don't want to do), but not delete. I have other pictures in other folders that I can delete...