This is a really interesting topic of conversation, because I'm just learning about the open matte format. I used to always think that if it wasn't 1.33:1 aspect ratio, it was panned and scanned, but I'm finding out that open matte is commonly practiced.
I'm finding out that if a film is exhibited at 1.85:1 aspect ratio, usually it was filmed at 1.33:1 (TV ratio) with the top and bottom shaved for the theater and then reinstated for TV. When a film is shot around 2.35:1, like Star Wars or The Apartment, there is no shaving on the top and bottom and so the film must be panned and scanned for TV. (Then there's Super 35, but that's a whole 'nother story)
So, for a moment I was thinking, "Hey, if it's a 1.85:1 film, I should get a version with the matte opened, so I can see the top and bottom. More picture = better." But then I learned more:
Two things usually happen. When filming, sometimes boom mics and sound equipment gets shot and the director leaves it in, knowing that it will be shaved off. When the film is shown on TV, you can see the equipment sometimes. Nowadays, you don't see boom mics any more, because the video producers still zoom up in the transfer, and then pan and scan, in order to get rid of the sound eqiupment. In other words, when your watching a film with the matte open, it STILL could be panned and scanned in places.
Number two: I discovered this when watching ALTERED STATES on DVD, which has the open matte on one side and the matted theatrical version on the other. Even though you're getting more picture on the top and bottom, the intimacy level is off from what the director intended. Medium shots become long shots, close ups become medium shots. Even though the fullscreen version has more picture, the letterboxed version of AS is better, IMO, because it's more intimate.
As far as Touch of Evil goes, I'm sure you can throw all of what I said above out the window, because it's Welles, and I can't begin to understand his genius. For me, I'm okay with my letterboxed version of TOE, since I've only seen the 1.33:1 version once in my life. The composition is fine, for me. It would have been nice to have the fullscreen version on the other side of the disc, and the commentary track, and the Reconstructing Evil doc, for that matter. Oh, well.
Jaime, why are you playing dumb with Rick about the aspect ratios? Bordwell's book goes into depth about that stuff. You have read it, right?