iDVD and an external burner or disc image
NO!
Although iDVD dosn't officaly burn to an external burner, there seems to have been some easter egging involved, and a lot of technical mumbojumbo that I didn't catch later, you can download two dinkly little pakages to enable it.
It is called, I belive, HPfurz, but a google search for iDVD easter egg will get you it. After you download it, take the photoshop files out of the folder they come in and place them into your home folder. Then, make up a dvd. When you are finished, hold down Control and click on File->Burn DVD...
Voila! A menu pops up that allows you to burn to a disk image or external burner. I prefer the disk image, then use a hard drive to move it to a computer with a Superdrive. Once there, Toast does its magic and I have a DVD!
These doohickies seem to work in conjunction with iDVD, but on occasion iDVD crashes, and you have to start over again. To try and prevent this, make sure that the computer never goes to sleep, never turns the display off whilst burning, and dosn't go into Screensaver mode. But at least, if iDVD barfs on the disc here, it isn't really a disc, (if you do the disc image option).
I don't think anyone will get angry at me for spreading the word...