Is it just a slideshow made up of pictures?
MM doesn't handle large numbers well, so how many do you have?
What size are they?
Have you used any transitions/effects?
If so, how many?
Did you add any music?
If so what sort?
It could be the complexity of he project, you could try splitting it into smaller sections and then bring all the saved files into one new project.
It could be the music files
It could be you need to upgrade your MM, graphics drivers, directx.
Which version of windows and MM are you using?
What are you trying to use to burn your dvd?
DVD maker?
Do you get the error if you just save the movie file?
You could then take it into dvd maker to make your dvd.
Do you have other dvd making software installed to try?