So I've played final fantasy 7 like twice or 3 times,
but never crisis core. I've heard it's a prequel?
Are Zack and Cloud like one in the same?
And what about Areith and Areis?
And I don't like the idea of it being on PSP.
Which is better?

Originals of a game 99% of the time are better.
I haven't gotten around to playing Crisis Core yet, basically cause I'm afraid it will suck lol...

zack and cloud are 2 different people

i dont want to give up too much of the story of crisis core but basically zack dies and cloud takes up his sword and assumes his identity so to say... still uses his own name, but claims he was a soldier first class (which he wasnt.. zack was)(ps this may seem like a big spoiler but you would know this from playing ff7 anyways.. you just dont know the whole story behind how it all went down, which is what crisis core is about)

aerith and aeris are the same person... it was just when the game was originally localized the names where switched up

and as far as whether or not to play it it is definitely worth playing

The idea of it being on psp though pises me off cuz it's such a small screen lol
I might play it though.
And ya I found out that he took over Zack's identity cuz Cloud's a little pussy LOL.
But I'd like to get in on the whole story.

if you have a newer version psp they can be hooked up to a hidef tv and played through the tv