Hypothetically, will this idea of ps3 games work?

remember this is hypothetic. i looked around looking to get free ps3 games and then i rea;zed theres no way to get 15gb on a reg disk. then i idea popped in my head remembering seeing and external hard drive (like a flash drive but way bigger) at walmart that holds up to 120gb. if i were to copy a ps3 disk using ulead dvd movie factory 6 and save the img file on the external hard drive then plug it to the ps3. am i a genius....i dont know.... only thing that freakin sucks is that my laptop dont read blu ray therefore cant copy the bleeping game.... but if i did have it...WILL IT WORK????