Higgins,
Open your presentation
Create a blank slide
Then "file>Save As.....
Then choose the "filetype" as jpg or similar.
Save the current slide
Then right click a blank area of your desktop
choose properties
Then "background" then browse to your newly saved jpg image
Cheers
TAJ Simmons
microsoft powerpoint mvp
awesome - powerpoint backgrounds,
free sample templates, tutorials, hints and tips etc
http://www.powerpointbackgrounds.com