Hey /vp/

So I'm about to go buy a previous gen pokemon game so I can pokegen and transfer etc. for x/y

Any of them in particular I should get?

I'm assuming black 2 or white 2 is best

Also how should I go about generating pokemon?

I doubt the ones generated via the app store will pass

And I can't find a site or link for a pokegen from my computer

Can anyone help me out?