No, PowerPoint doesn't save presentations in any video or audio format.  To
capture a presentation as video, see the tutorial at
http://www.powerpointbackgrounds.com/powerpoint-to-dvd.htm.  Though targeted
to DVD, the capture portion of the tutorial is applicable to your question.

Hello,

PowerPoint for Windows does not have the built in ability to save
presentations as video files or any type (with the exception of PowerPoint
97 using an obsolete add-in from the Windows Media Technologies team for
converting a presentation with narrations to an *.asf file).

If the ability save presentations as video files, directly from within
PowerPoint, is important to you (or anyone else reading this message), OR
if there are specific features of PowerPoint slide show that you would like
to see (which would mitigate the need to save presentations as video
files), don't forget to send your feedback (in YOUR OWN WORDS, please) to
Microsoft at:

http://register.microsoft.com/mswish/suggestion.asp

As with all product suggestions, it's important that you not just state
your wish but also WHY it is important to you that your product suggestion
be implemented by Microsoft.  Microsoft receives thousands of product
suggestions every day and we read each one but, in any given product
development cycle, there are only sufficient resources to address the ones
that are most important to our customers so take the extra time to state
your case as clearly and completely as possible.

IMPORTANT: Each submission should be a single suggestion (not a list of
suggestions)

In the meantime here are a couple of free Microsoft downloads for capturing
(recording) what's on your computer screen (including a slide show in
PowerPoint):

1) Microsoft Windows Media 9 encoder

and if you are using PowerPoint 2002 or 2003...

2) Microsoft Producer 2003 for PowerPoint (use it's screen capture
capability during a PowerPoint slide show).

Both of these create *.WMV files which are the same as *.ASF files (just a
different file extension). In each case they only capture the screen and,
optionally, the default audio input source (not output) so to record audio
you would have to use an audio patch cable to connect the line-out or
speaker-out port to the default audio input port on your system. If your
slide show contains any video, it would not be captured.

Here's a recently released app that converts ppt to dvd...

www.geovid.com/Presentation_to_Video_Converter/
try this!