What is the optimum size/resolution settings for photos used in P.

[jrbpub]

I'm adding photos to a presentation and want to size the photos for optimum
viewing. What dpi should I use?

 

[J Terberg]

DPI is irrelevant for on-screen presentations. Full-screen images
should be sized (in pixels) equal to your computer display setting
(typical: 1024x768). Smaller images - size them down accordingly. Half
screen: 512 x 384, etc.

For more info:
http://www.rdpslides.com/pptfaq/FAQ00415.htm