Not sure which WATCHMEN to get on blu-ray, what is the 'best' version of the movie? theatrical, director's or ultimate cut?

You can't buy the theatrical on Blu-ray. It does come as a digital download on the Director's and (I think) Ultimate. Director's is definitely a stronger movie than theatrical. I haven't seen the Ultimate cut.

I prefer the director's cut but the theatrical is good too. It is VERY long but worth it so I'd go director's cut. Ultimate cut seems stupid to me.

I actually prefer the directors cut over the Ultimate; even though they segue "Tales of the Black Freighter" seems out of place.

Director's cut was much better, erased the few ambiguities, added more Hollis Mason, a few nicely done shots (the Comedian's slow decent in the Huey in front of the towering Dr. Manhattan in Vietnam), and was a great movie, I wish they'd been able to release that in theaters.

Yeah..the Hollis mason bit was great...probably my fav scene. HATE the acting by the 2 gang members though before the Hollis scene.

I'm waiting for the "Boom Stick" edition.

Director's Cut for anyone who hasn't seen it or is a relatively casual fan.

Ultimate Cut for the hardcore fans who want something as close as possible to the "graphic novel" experience without reading the graphic novel or watching the "motion comic."

The cut that doesn't exist. You'd probably want the Director's Cut though.