Greg - it was my understanding that 1080p is 1920 x 1080. While that's not the full 2500 x 2500 of the pix, it's pretty damn close, and for public, "together" viewing of pictures, the best possible. Remember, Kodak stopped making slide projectors, which is the old way of getting the family round the screen for a group appreciation of my hard work kind of night.
So, the computer monitor looks darn good at 1600 x 1200, I'm hoping that if I get this right, 1920 x 1068 will be ok. I lose a bit, but not much, and again, not much choice, just trying to optimize.
Kneedragger -- If I'm able to disguise the fact that it is a game console, it might be the way to go (or a PS 3). Again, I'm thinking (and I may be wrong about this) that more control over the content than just time between slides is what I want, but I may be wrong there, too.
Thanks folks. Still plugging away at this conundrum.