technically its not legal, as you have to bypass the copy protection the copy an image to the hdd, but noone would do you for it, because logically it should be legal. i think saracen mentioned that they were looking at altering the law.
it goes the same as ripping songs to put on an mp3 player, thats technically illegal too.
so technically this post IS discussing illogical illegality

but of course your not going to be arrested for it because some companys push software to rip songs to your mp3 player. technically WMP is illegal
how long till someone turns up and proves me wrong
getting back to the subject: i recommend imgburn (i'm sure that can create iso's from a disc, if not ill go have a hunt on my computer)