I'm a big fan of Star Trek, especially the original series.
Recently I was thinking, how would the original series hold up against contemporary television shows? The scripts and acting were excellent, and the image quality holds up quite well as it was made on 35mm film. I think there is only one area where it would be lacking and that is the special effects. While spectacular for their time (1966-1969), modern audiences are used to computer generated images (CGI). The original series primarily used models and matte paintings, which limited what could be done.
Maybe someone at Paramount studios had the same thought. In 2006 they began syndication of a new version of the original series that was rendered in high definition with new CGI visual effects. Most of the external space shots of the Enterprise and other ships have been redone, and many bridge viewscreen images have been updated. But the live action has for the most part been left original, other than being cleaned up for high definition.
I recently received a DVD set of season one of the original series as a gift. After viewing the season one episodes I decided to buy season two. It seems that Amazon is no longer stocking the original DVD set, but the digitally enhanced version of season 2 was just released, so I bought that instead.
Overall I like the new version. The DVDs are similar to the original set, but have s few more extras. Apparently this was originally planned to be a hybrid DVD/HD-DVD set but the HD-DVD format was dropped when BluRay won the format wars, so the discs are one-sided but unlabeled as if they should be double-sided.
I was afraid that the new effects would be glaring when interspersed with the old footage, but they're pretty subtle. Take, for example, the episode The Doomsday Machine. There is a shot of the USS Constellation lying damaged in space. You can see some rocks or other debris around it, and in one shot a rock actually bounces off the ship's saucer section. This is something that wasn't feasible in the 1960's when they used models of the ship. (In fact, an interesting piece of trivia about this episode is that the model of the USS Constellation was actually a commercial plastic model kit that the effects team purchased, assembled, and added some damage to. The ship's registration number -- NCC-1017, used the included decals from the Enterprise, NCC-1710, with the numbers rearranged).
The digitally remastered version was controversial among Star Trek fans. Some felt it was tampering with perfection. After viewing a few of the episodes, I like it.
Although it is hard to believe, there are people who have never watched the original series. If the digitally remastered series exposes more people to the show (either on television or by purchasing DVDs) then its a good thing for Star Trek fandom.
So when it comes time for me to buy the season three DVD set, which version will I go for -- the original or enhanced? I think it will be the enhanced version. (That's assuming I buy the third season at all; it's definitely the poorest of the show's three seasons. But then again maybe new special effects can salvage my choice for the worst episode of the series The Lights of Zetar).
You can get the Star Trek DVDs as individual discs, boxed sets for each season, or as a boxed set of all three seasons. It's available from a number of sources such as Best Buy, Future Shop, or on-line from Amazon.
Wikipedia has more on the remastered series under the entry for the original series.
Youtube also has some clips of the new CGI scenes, including some side by side comparisons of the old and new.