I’m a bit of a film buff and if I really want to watch something, I will check netflix streaming, amazon prime, and hulu streaming. Then the library. then if there’s a long wait there, I will go to redbox. If it’s not there, then streaming rental for pay (iTunes or Amazon watched on the tv). If I really, really want to see it and think there’s a huge chance I will love it, then I will buy it on blu ray. Otherwise it goes on a list to watch when it comes out on netflix or digital rental.
Practically, I almost never end up buying DVDs of movies I haven’t seen. If it’s something I am desperate to see, I will see it in the theater. Everything else comes onto digital rental soon enough. I buy DVDs of films I love and will watch multiple times.