Don't do this. Why? Because HD DVD lost out to BluRay in the high def DVD wars (like Betamax lost to VHS back in the day). The only devices that will play those DVDs are Toshiba HD DVD players that have been discontinued for about 4 years. And Macs with Superdrives. That's it. Regular DVD players won't play them, BluRay players won't play them.
If you want high def DVDs, you're going to have to invest in a BluRay burner, and software that will author BluRay disks, like Toast. Compressor will author BluRay, to regular DVDs no less (so I hear), but they have to be under 10 min. And then those will only work in BluRay players.