Keynote: Exporting a presentation from Keynote to iMovie
http://support.apple.com/kb/HT2655
Burning Keynote presentations in iDVD
http://support.apple.com/kb/HT2936
Contributor Old Toad has added the following excellent advice:
To get the keynote presentation into an iDVD slideshow that you can advance slide by slide with a DVD player remove you need to convert each Keynote slide to a jpg file. To to this go to the view all slide window, select all of the slides and type Command+P to start a print job.
While in the print window click on the PDF button at the bottom and select "Save PDF to iPhoto" from the drop down menu. That will create a 200 dpi jpg file of each slide of the presentation.
Next add those slides to a slideshow in iDVD and select slide duration to Manual. Now the finished DVD is played the DVD player remote will control the advance of the slide.
I suggest you follow this workflow to create the DVD:
Once you have the project as you want it save it as a disk image via the File ➙ Save as Disk Image menu option. This will separate the encoding process from the burn process.
To check the encoding mount the disk image and launch DVD Player and play it. If it plays OK with DVD Player the encoding was good.
Then burn to disk with Disk Utility or Toast at the slowest speed available (2x-4x) to assure the best burn quality. Always use top quality media: Verbatim, Maxell or Taiyo Yuden DVD-R are the most recommended in these forums.
As far as having no menu you must have a menu to fall back into once the presentation has finished. If you want just a black screen use one of the old themes like Brushed Metal, Burlap, Sage or Graphite and put a blank, black image file in as the background. You will have to have a button or text button in the menu so choose text and set the text to black if you want a fully blank menu. Be sure to set the highlight color for the text button to black also.
Finally follow Klaus1's method of dragging the slideshow into the autoplay bin while in the Map mode so the slideshow will start automatically when the disk is inserted into the player.