My dvd player cannot read jpg files.
Wwhat is the most common photo format that all dvd players would support? What should I convert my photo files to to play them on my dvd?

JPG IS the most common format. But not all DVD players can play stills. Check your operations manual.

You are using right format but are u using the right disc format? Most dvd players will not read dvd rom or dvd jpegs. They need to be on a CD not DVD! This is a big difference because the dvd player can only read jpegs if they are on a CD do to the format. Make sure it is a cd u are burning the jpg files to.