Best settings for slideshow, destination DVD

Could anyone throw a little light on correct settings form making a slideshow, to be burnt onto DVD, to play on DVD, or maybe DVD on Computer.
My .jpg photo sizes are 3072x2304 pixels - first should I use settings for standard or widescreen, when creating slideshow with photos in this ratio.
For each then, Standard or widescreen, which settings should I use adjusting custom settings. e.g 1440x900, comes up on Fotomagico, or 1000x700, or what? Have been told that you do not need such high settings for DVD.
Then when burning what settings do I set there. It sometimes asked if you want cropped or letterbox to overcome differences in project settings.
So far, with different settings, I loose some of the Titles when set along the bottom of the picture. and/or get stretched images of people.
Little confusing for new user