I'd prefer a proper HD remaster of TMP. The one I have (which includes the other 5 movies on DVD) has a lot of frames where one side is nice and sharp where it's been remastered. But on the other side of the frame it's just as blurry as before.
I clearly remember the scene where spock comes onto the bridge for the first time. kirk gets out of his chair and gawks at spock. Everything on the right of the screen (in front from kirks view point) is nice and sharp but on the left (behind kirk) it's incredibly blurry. Really really poor job of that one I'd say!
Plus it isn't even the directors cut with the CGI vger. I was devastated as I've never ever seen this directors cut version of TMP. And I paid ?40 for the box!
TWOK could do with a nice remaster. I can imagine what they could do with good cgi too! And just picture the destruction of the ent in TSFS if it were in HD!
ST4 would be cool, but I'm not sure you'd need much cgi there! What about redoing the SFX of ST5? might improve the film slightly.. But TUC would be far more deserving of proper CGI and a HD remaster.
But at the end of the day, I'd like to see EVERYTHING remastered in HD