ACDSee Picture Frame Manager Software

"ACDSee Picture Frame Manager software for Mac and PC allows you to conveniently manage images for any type of display device. Whether it's a photo frame or a large screen 1080p TV, this application will optimize your images to the resolution of your frame so you can fit many more images into the frame's memory with ease."

I think you can file this under the "for n00bs" only category, but if you know someone that has a digital photo frame and they struggle with getting their images re-sized, this might be a good solution - albeit an expensive one at $39.99 USD. There's not a lot of descriptive text, so maybe it's smarter than I'm giving it credit for. If it could detect (or be told) the aspect ratio and resolution of your frame, it would be slick to have it not only resize the images but also automatically crop them to the right aspect ratio. Point and shoot digital cameras typically take pictures in a 4:3 aspect ratio, while most DSLR cameras capture images in a 3:2 aspect ratio. Nobody likes to see black bars on their digital picture frame, so this might be a solution.