Unless they really bungle the mastering of a BD, you should always buy the BD instead of the DVD (if a film is released in both formats) no matter what the movie is. You can check reviews of particular discs at various sites online; here is one:
http://www.blu-ray.com/
Even if you now have a small TV that you sit so far away from it that it makes little difference, it will matter when you upgrade the TV in the future, and then you will be glad to have the BD instead of the DVD.
