I have Blade Runner on bluray, although not the "ultimate set", just the final cut. Don't know if there are any differences, but I'm guessing there isn't. I think it's really good, and I'm a big fan of the movie, but The Dark Knight should be the first choice for you. And everybody else
I also own Wall-e, and that's brilliant as well. In truth, Wall-e may be even better looking than TDK. But it's an animation, it doesn't have the same effect as TDK.