DVDs up-converted to 720 from a Mac?

As I've previously posted, the Planet Earth series on Discovery Channel was eye-poppingly amazing on our Toshiba plasma TV. Definitely worth filling up the HD DVR with those episodes.

My lovely wife noted how much I liked Planet Earth and got me the HD DVD version for Father's Day. The only problem: we don't have a HD DVD player in the house. So, she exchanged for the standard definition DVD format, and, wow, what a difference it makes (unfortunately, not in a good way). I miss my Planet Earth in High Def!

Back in January, I blogged about our A/V tech stack, and you'll notice there's a distinct lack of a DVD player in there outside what's available via our Mac mini. So, I see a couple paths ahead:

1. Get a new standalone DVD player (HD? Blu-Ray? which format's gonna win?) and figure out how to get yet another HDMI cable into and through our HK AVR245. (a DVR and a Mac and a DVD player, oh my!) The AVR245's only got two HDMI inputs, and I'm reaaaally reluctant to go back to an external switcher, especially given the 245's handling of the audio separately from the video.
   
2. Figure out how to get an HD player inside our Mac Mini (highly unlikely, but a man can dream, no?)
3. Figure out how to get our Mac Mini to upconvert the DVD it plays from 480 to 720 (feels like this could be a fruitful path)

I'll give #3 a shot and blog about my progress.

UPDATE: Didn't take too long to find the following sage advice (dollop of common sense?) in an HD forum regarding upconverting from 480p to 720p:

[I]f you're expecting the results to look better than the original standard-def DVD, you'll be disappointed. There is no conversion process that can add detail that isn't present in the original. You will in fact lose some quality because the target resolution isn't an exact multiple of the original.

Looks like I'll just have to "settle" for the standard-def look and enjoy catching Planet Earth on Discovery HD now and then.