transcoding/burning DVD takes 10 hours! whats the alternative?

Understood.

One question about coding however:

I have made a few minor changes to the original movie (deleting scenes, adding transitions etc), since burning to DVD.

-would I need to go through the whole lengthy encoding process again, either via the 'normal' route or via disk image, or would it only update the changes?

Yes, unfortunately. iDVD has no record of which
changes you have made.

would another app. e.g FCP or DVDSP be any different in this regard?

I wouldn't normally, but in this case I noticed, on playing the DVD that I'd accidentally included a scene and long transition, which I'd meant to omit.

Now that I have to redo it anyway, I want to make two versions, one with additional material, one without. (one version is a christmas present for a family member so has specific material on it - the other is for wider distribution for friends)

Its just a pain to have to do the whole thing twice over when 90% of the footage is the same in each case. Perhaps someone could write an application which would solve this...

I'm not talking about splicing - although in this particular instance it may be a solution.

The situation is this:

I filmed a performance of a classical concert, in which a family member took part. The concert itself is 1.5 hours in length, of more-or-less continual footage (though I did insert a few transitions, and substitute still shots, while maintaining the sountrack, where the footage suffers overly from camera-shake).

at the beginning and end of the concert footage, I appended 'prologue' and 'epilogue' footage,-additional material specific to the family member concerned, plus start and end titles. I then 'created iDVD project' - the coding of which took the bulk of the time, and burned the dvd.

On playing the dvd for the first time on my Alba DVD player (incidentally, I couldn't play the disc on my Pb which created it - got 'disk not supported' message), I noticed that I had accidentally included a 'blank' clip where one shouldn't be, between two 9.27 minute continuous footage clips. So that had to be taken out.

This means I have to go through the whole encoding process again, for the sake of one tiny edit.

Additionally, I have had several requests for DVDs of just the concert footage itself, minus the 'prologue' & 'epilogue' bits. So I will have to create two disk images and encode them each seperately, each taking several hours, although the footage is 95% the same.

I am sure there are plenty of people with similar scenarios, where they would like to tailor DVDs for different audiences without having to go through the lengthy encoding process for each minor variation. this is the issue - not the burning time. That I can live with, without even getting a stand-alone burner at this stage.