Nero 6

HI, I am not great with computers so I am having great problems with my dvd rewriter which came with nero 6 software and lg program as it is a lg rewriter.
All I want to do is save my pictures to a dvd, I have both dvd-r and dvd-rw but i can only put the latest pictures to a disc, it will either make any pictures on the disc unaccessable or wipe them of the disc.
If anybody can help a dunce like me I would be very grateful as will the rest of the family as I would stop swearing at the computer.