Backing up HD movies to an external hardrive

[Blueface]

I recently purchased an HD video camera that relies on a flash card for memory.
I want to save the file, in addition to burning a DVD.
On my Mac, on iMovie, it imports it as an "event", which is the raw footage, unedited.
From there, I create a "project", which is the cleaned up movie, with transitions, effects, etc.
From there, I create an iDVD file as result of the final process, allowing me to not only burn the DVD, but also add themes that are very nice, to give it a professional look.

So, I have three files.
I know the evident difference between all three.
One is raw as shot.
One is edited from the raw.
Last one is the final product.

I don't see need for all three and they collectively consume too much space,
So.........which would you save?

I know opinions will vary but that is what I want to hear.
I'm truly tossed.
Wife says keep the original raw one. I say keep the final one as that is what I want to see in the end.