My question would be: How do you expect this movie to look? I own the HD DVD and find it to be very faithful to the original soft look of the film. This is not a movie that will exhibit a 3-D "pop" like more recent films or older, large format films.
I am using HDMI, the display is properly calibrated. I just don't think it looks that much better than the upconverted SD-DVD. Just my opinion. Probably the way it was originally shot. Soft and lots of matte shots and green screen.