So, over the weekend, I watched the first four Trek films on blu-ray. I bought the "original motion picture collection" that contains the first six Trek films with the original cast, but ST V and VI are my least favorite of the six.
My first observation is that I'm a bit surprised by how soft Wrath of Khan looks compared to the others. Since the other films look pretty sharp in comparison, I have to conclude it's not some problem in the digital transfer, but that Wrath of Khan had an inherently softer picture. I don't know why. Maybe the film stock used for that movie was subpar.
The other thing is that I'm disappointed that these blu-ray versions aren't the "Director's Cut" versions as released on the earlier double DVD sets. Rather, the blu-rays all appear to be the original theatrical versions. It's especially disappointing in the case of The Motion Picture. For the DVD release, Robert Wise and company had given TMP a lot of TLC, restoring it to its rightful place as a sci fi masterpiece (in my opinion). The Director's Cut of that film was as definitive as one could have hoped for.
The most pleasant surprise of the bunch, image quality-wise, was The Search for Spock. I couldn't believe how clean and crisp the picture was: it jumped out at me. The Voyage Home looked very good, too, though it didn't knock me out like Search for Spock.
Also, in watching ST III, I was struck again by its bittersweet quality, an emotional vulnerability - and grace - that is unique to it. That was the genius (if I may call it that) of the film: that the whole thing revolved around getting Spock back, so that when Spock did return, it felt like a hard-earned return. ST III did an extraordinary job of making Spock's return not look like a big cinematic cheat. Imagine if there were no Search for Spock, if they went right to Voyage Home and Spock's resurrection only occupied the first 10 minutes of the film before everyone went to save some whales. Oh, and I'm more convinced than ever that ST III represents Kirk's finest hour (and a half) on the big screen. Montalban may have owned Wrath of Khan, but the depth of feeling Shatner puts into Kirk in ST III is something special, too.
The Voyage Home, meanwhile, remains the most fun Trek film ever. The camaraderie here has never been matched. I like to think that, in some alternate movie universe, Kirk and crew went on to more awesome adventures after they had boarded their new Enterprise at the end of ST IV.
The new bonus blu-ray features are, annoyingly, randomly inserted in with material previously released on the DVD sets. Not that there's much in the new stuff, as the material from the DVD releases was already fairly deep. I haven't listened to the new commentaries - that may be the only way that I'll sit through ST V and VI.
Haven't watched it yet, but this blu-ray collection also has a seventh disc called "The Captain's Summit" - a round table discussion featuring Shatner, Nimoy, Patrick Stewart, Jonathan Frakes and Whoopi Goldberg. (Gee, Goldberg was a starship captain on Trek? That's news to me.)