Yes, you can have it reprinted elsewhere, assuming that market accepts reprints (and you of course tell them beforehand). Archival rights are just as the tin says. The right to keep your work in the archives. With Peccary Magazine, I ask exclusivity for 1 month - you can't publish it elsewhere during that time. After that, I ask for permission to archive the story for at least 3 months. After that they can ask for it to be removed, but of course, I'd prefer they'd keep it there.
You might want to make sure how long they want those archival rights and if you can retract them after a certain period of time.