Backing up to DVD

[Bokuden]

I reacently installed a Magic 3 mod chip on my ps2 and am now attempting to make a backup. I have seen alot of info on how to backup to a CDR but not a DVD. I am usuing dvd+RWs which i read are saposed to work fine with a magic 3 chip. Basicly what i did is took my Vice City game and made an image with nero then attempted to burn that image. The burning was sucessful but the game won't play in my ps2. Obviously i am doing this wrong so what is the correct way to backup to dvd?