I think you can pick up a blu-ray drive for around $55 on amazon US. That's not really a huge endeavor, and it's worth it, you'll definitely use it.

What I would hope, is that the 5.1 surround sound track on the blu-ray is mostly just dialogue and sound effects, and the music doesn't bleed over. If that's the case, you can deleted everything but the center track and completely rescore the movie. Unless it's like the Star Wars DVD's, where the music bleeds to the center channel, then it will be a bitch.