The first time I saw this 1961 film, it was in Spanish class in High School, well after its theatrical run. By the 70s, the musicals weren't being shot, so West Side Story is a product of its time.
If you've never seen this classic, it's basically a re-working of William Shakespeare's Romeo & Juliet with two star-crossed lovers from rival gangs, the Jets and the Sharks.
I found that the remastered DVD looked just as good as the Blu-Ray, so if you do not own an HD TV or Blu-Ray player, you may be just as happy with the SD version of the film... however, it's inexpensive, so throwing in a dollar or two for the HD version might be worth it in the long run.
Of the three editions that I own (DVD Collector's Set, Target Edition, and Gift Set), I have to say that the 50th Anniversary Gift Set is the best one to get. The Tribute CD's track listing is not printed anywhere on the gift set (except for the throwaway sheet that describes what you get in the box), so I suspect this was tack on at the last minute. The bonus features and transfers are the same as the Target Edition.
While I would actually not buy the movie as a bare-bones release, getting the extras at a reasonable price, I do highly recommend it. Sometime I would regret owning various editions (like Evil Dead), but not with these West Side Story editions because they all have unique offerings. If someone would just combine all these features into one "Ultimate Box Set"... I would buy it again.
West Side Story: Sharks vs Jets