Nope, they don't show even if you turn on "show hidden...". Not THESE files. They can not be accessed or deleted by Windows Explorer or Internet Explorer. The only way is by DOS, if you know exactly where they are. You can't even find them by executing the "DIR" command... :inquisitive:
And the reason to delete them is not so much privacy. Just doing a virus scan take alot more time when there is thousands of old files to search. (And yes, just doing a normal delete doesn't actually remove them).
I personally don't bother so much deleting that junk, but it's still interesting to know about it.