If you want to keep it hidden, keep it hidden.

If they checked your background and most of the checks find nothing, but one does turn up something, now all they have to do is google "arrested 2005 in Texas for peeing in public" and this page is the first link that turns up. So then they would be able to see your post and understand your dilemma. I think it'd be a little bit rediculous to deny someone employment for a minor incident like that