Rainer T , Feb 22, 2009; 01:32 p.m.
-- "I was thinking 700 KB which is 300 DPI at 6 X 4 size."
Too big ... you're feeding the frame a 1800x1200 pixel image. The display of the photoframe will have a much smaller size. Something like 1024x768 of 800x600 is more likely.
When I copy images to the photoframe of my parents in law, I resize so that the long side is 800pixels (they have a frame with a 800x600 display), and store with 95% jpg-quality. The filesize I get is about 150Kb.