Burning with disk juggler

i burnt the utopian boot cd with nero, with no problem and tried burning my first .iso file with disk juggler. when i put the cd into the dreamcast the boot cd changes and ####ts loading the game, but then when it reaches a 100% the screen goes white and the dc ####ts making very bad noises, kinda like snoring, anyway, could someone tell me what i've done wrong here, like i said the boot cd is fine but i'm obvisouly burning the game wrong. thanks for your time.