Final Fantasy 7 in PSP...as good as the movie? Does it tell the whole story of Cloud, about his childhood?

I'm going for vacation in a few months, I know Ps3 is coming out soon n I can play FF7 in it but I'm not gonna be here at that time and I cant take the Ps3 with me..so I thought I'll buy FF7 in PSP and take it with me. I tried to search its demos but the graphics sucked, its not like it is in Ps3 u see? I just wanted to ask if there is a game of FF7 in PSP as good as the movie graphics? Or will I just have to wait till march. I'm going to buy the PC game because I've heard there's his whole childhood story in it (Is it called FF7 Advent Children (for PC)?) but its graphics suck too but thats ok as long as there's his childhood story in it..and about how he meets Aerith. And..thats all I guess. Thanks for helping!