The 'I wish I were' form is generally used when referring to something purely hypothetical..ie something that just ain't gonna happen! "I wish I were Prime Minister" for example.
(The subjunctive mood, which this is, is enormously complex...the standard reference work on English syntax takes 156 pages to deal with it. Accordingly, I'll leave it at that!)
The first one is correct. It is usually used in the subjunctive mood."I wish I were a wishing star." for example, means that I would never be a wishing star but I just wish to.
runs and hides don't ever mention a subjunctive to me again! In all honestly I speak the spanish that I hear (colloquial?) and wouldn't know a past-participal or subjunctive if I was dancing the flamenco with it. Sorry. for example " I go yesterday to doctor" see what I mean!