Hey!
As for which to choose from Black or White, it really doesn't matter as I said. :p GameFreak did announce, though, that you should get the sequel of the first game you originally chose. This means that they recommend that if you got Black 1, you should get Black 2 as the sequel game, or if you got White 1, you should get White 2 as your sequel game... I guess to make sure there aren't any errors in continuity in stuff. After all, they are sequels. :p