Parallax would destroy Batman in seconds. As far as good ol' peak of his career Hal, it would be a great fight. Aside fromt the whole yellow thing, Hal's only weakness would be Batman distracting him so he wouldn't be able to use the full power/effect of the ring. The fight would be over, however, if Hal was to use the ring to create an oxygen removal device around Batman and choke him to death. But I don't think Hal is as sick and twisted as me.
Although Kyle's GL ring is more powerful, in any confrontation with Batman I would say that Bats has the upper hand.