Whoa... DVD Decrypter is one of the easiest programs ever! Just set to "ISO --> Read" then click the big "Decrypt" button. Then "ISO --> Write" and write to your blank DVD with the "Decrypt" button (after you locate your iso)...
If that doesn't help, there is a tutorial on it here:
ALLERGY ALERT: The above post may be nuts.
N64, GBA, both un-modded.
NTSC U/C PS2 v4 w/No Solder v4 (SOLD, DRE... Laser Died
NTSC U/C PS with Plugmod (SOLD to pay for above