let me guess, the old, "service pack installed gigs of porn" issue. notwithstanding the files created and modified dates are long before when the service pack was installed.
Mother: what are these? sexy blonde.jpg? hmm. must be ... *censored*! BILLY! GET IN HERE!
Billy: What.
Mother: WHAT is this?
Billy: Oh erm... I installed service pack 2, there's a err.... known issue, with it accidentally downloaded thousands upon thousands of innappropriate, high resolution images.
Mother: Well, by golly it's destroyed our PC! there's absolutely no room left! Although I think it's the same amount of room as we had before the service pack, but what do I know!