Here's something I found on the web.
This is a direct quote from Adam Crowley, who is well
known on the PowerPoint newsgroup for his knowledge of
and experience with PowerPoint and video:
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It can be done but is far from simple and may give
disappointing results.
The easiest way to get a good result, if you have the
equipment, is to use a TV-out graphics card to output
direct to a DVD recorder.
The next easiest way, if you have access to a Mac with
either Office 2001 or X, would be to save your PowerPoint
file as a Quicktime movie, convert this to a DVD
compliant MPEG2 file and then author the DVD (Ulead have
some cost effective, if limited, DVD solutions).
www.ulead.com
Then there are several products that capture screen
motion to a movie file (camtasia and hypercam to name
two). Beware, you'll almost certainly find that with
these products you can produce either high resolution but
low frame rate movies or low resolution movies at full
frame rate. Both of these outcomes will give poor results
that do not take full advantage of the quality DVD can
offer.
If you use one of the above methods, the DVD will not
have any "cueing" or navigation. You will need to add
that using your DVD authoring software.
A few guidelines to be aware of when creating graphics
that will be shown on a TV/video monitor:
1) TV interlacing makes thin lines, particularly
horizontal lines, shimmer like crazy. Thicken up all your
lines.
2) Keep charts and detailed diagrams simple - you'll have
trouble reading complex detail at TV resolution.
3) Avoid very saturated colours, especially bright red.
4) Understand that on a TV monitor you don't see the
whole picture - work to a 'safe area' (i.e. leave at
least 5% of the width and height at the edge of your
slides).
It will help you see what works and what doesn't if you
can connect a TV-output to your TV as you work.
All of these options assume that you have transitions and
animations that you want to preserve. If not then the
simplest and quickest solution of all is to use another
product, which allows you to string together a pile of
images into a self-running DVD slideshow. In particular
it's worth looking at some of the products that are
specifically geared towards photo slideshows on DVD (i.e.
not using PowerPoint at all).
Ulead's DVD Pictureshow
http://www.ulead.com/dps/runme.htm
DVD Photo Slideshow
http://www.dvd-photo-slideshow.com/
Photo2VCD
http://www.photo2vcd.com/
And there are probably more if you do a search for DVD
Photo Slideshow. Some, if not all, of these products
allow you to put a soundtrack to your show. It's much
easier than what you'd have to do to get a good result
using PowerPoint.
Adam also recommends Roxio Easy CD & DVD Creator 6 from
http://www.roxio.com/en/products/ecdc/index.jhtml