Free image editors such as Picasa offer one.
Irfanview is another.
Simply burning the images in the root directory[not in a folder is another.
Much depend on the DVD player.
There are many 'Chip sets' employed in the many and varied makes of player and the types of 'Burned disc and the playing methods very enormously.
Also no player will play an 'open' disc they have to be finalised.
A good read of your players manual will tell you more