I agree; the sound is fantastic. The picture is solid, but unspectacular. However, this is a source not transfer issue. All in all an excellent representation of the film for fans.
Professional standard is 48 kHz. 96 kHz is very unusual, except for specialty audio recordings such as those originated with the express intention of releasing them on DVD-A. The likelihood that there is a 96 kHz master tape for this, or any other, motion picture is very small.