Star Trek Voyager Dark Frontier episode and First Contact

So, I'm in looking for two things, maybe is hard, but try to not give me spoilers.

1. Is the same Borg queen?
2. The movie was before season 5 of voyager, right? How Janeway came back at that time? Maybe it will be explained later in the Voyager serie (I can figure out a time travel or something) in that case, at the moment of the movie, nobody ask how Janeway contact Picard?

EDIT: Nevermind, Janeway appears in Nemesis, not in First Contact.