If you're going to create a DVD, you might as well create an MPEG2 file at this stage. iDVD was probably giving you errors as it didn't recognise the file you're creating using those above settings.
Follow the first steps in the link I provided in the other thread here
http://www.videoeditingforums.co.uk/...ighlight=#3445
Then use the created MPEG2 file in you DVD authoring application.