Great stuff Alan. Here is what I did.
Using the now unsupported iDVD within Mavericks December 2013.
After editing and creating a Movie or Movies in iMovie do Share.
Then select File
Then using the selection up and down arrows within the dialogue box select Large 540P(960 x 540) According to other members this is due to the Superdrive in the Mac outputting a maximum of that quality which is OK for Standard Definition. I also found that, for me, selecting a larger format failed during processing.
Select next then give your File a Name and Location on your hard drive.
Note:-
This takes a while and there is no indication that anything is happening!
The output is the edited Movie and is created as an MP4 file. Once you have your Movie or Movies prepared as MP4 then you can continue to iDVD.
At this point you can use iDVD in the normal way except that to input your Movies you just drag and drop the files into the respective Drop Zones.
Finally burn your Movie (I used DVD-R) this is time consuming and takes almost real time outputting to the DVD.
Note:-
I found that using Standard 4:3 as the project format gave the best results on my widescreen TV. If you use widescreen when creating the project even if the images are kept inside of the boundary lines on the TV the picture bleeds off the edges of the screen. This is in the UK on a PAL TV. I also found that widescreen taken from my Humax Box and created as a DVD created an image that bled of the edges of the screen.
In general I am happy with the output but would happily take more advice on perfecting my projects.