And the third and final part? Because the Blu-Ray release is Urusei Yatsura 2 Beautiful Dreamer, which was written and directed by another legend: Mamoru Oshii. The film was originally rejected by Rumiko Takahashi and most Japanese anime fans because it's such a deviation from the series' usual style and tone, but it's always been a hit with most American fans and has done reasonably well in Japan (which the BD release should more or less prove).
So! If you were going to spend $50 (pre-shipping) to import some hi-def anime, I'd suggest this as a possibility. Unfortunately, it has no English subtitles-- which is especially a shame since it does feature an audio commentary that includes Oshii himself.