This is a rather good list a guy made some time ago but I have several of these HD-DVDs and this information is correct to my knowledge, especially in regards to discs such as The Deer Hunter, Animal House and The Thing.
from AVS Forum...
"I have personally confirmed the following HD DVDs look better than their Blu-ray counterparts either due to better grain structure, less contrasty boosting, or both:
RELEASES THAT LOOK *MUCH* BETTER ON HD DVD than Blu-ray
Animal House
Apollo 13
Army of Darkness
The Big Lebowski
Coming to America
Daylight
The Deer Hunter
The Sting
The Thing
Waterworld
RELEASES THAT LOOK *SLIGHTLY* BETTER ON HD DVD than Blu-ray
Casino
The Mummy
The Mummy Returns
U-571
RELEASES WITH BETTER AUDIO ENCODES ON HD DVD than Blu-ray
The Lady in the Water
RELEASES THAT LOOK SIGNIFICANTLY BETTER ON BLU-RAY THAN HD DVD
12 Monkeys
The Breakfast Club
Flags of Our Fathers
Miami Vice
RELEASES THAT ARE CONFIRMED TO LOOK SIMILAR ON HD DVD & BD
An American Werewolf in London
Billy Madison
Bulletproof
Darkman
Dune
Fast Times at Ridgemont High
Happy Gilmore
Tremors
Most Warner/Paramount titles unless otherwise specified.
RELEASES THAT LOOK and SOUND BETTER ON STANDARD DVD than any HIDEF release
The Last Starfighter (1999 CE DVD - Blu-ray / HD DVD extremely DNR'd and has missing audio cue)
RELEASE THAT HAVE ORIGINAL SOUNDTRACKS ONLY ON DVD, HIDEF only have modified SOUND EFFECTS or MUSIC
Conan the Barbarian series (Blu-ray music problems)
Smokey and the Bandit (DVD Pursuit Pack - HD/BD dont have original sound effects)
Terminator (extremely old Image DVD is actually best mono track - HD/BD dont have original sound effects, subsequent DVDs have comparatively poor bass on mono track)"