Technically yes, but it would actually be a whole new Earth. To quote ST 2:
McCoy - "What if this thing were used where life already exists?"
Spock - "It would destroy such life in favor of it's new matrix."
So the Genesis device...had it worked...would constitute a failure of this RAR.
Finnnnneeee, I just enjoy quibbling with semantics
Well we know from Alien 3 that Xenos won't attack humans who have been infected...and people in the hive only ever get implanted once...they don't get loving from more than one. So obviously there's some kind of marker that prevents these sorts of things, like a pheromone. So if that's the case, they could just mass-produce this stuff in the form of a body spray or...heh...*bug* repellent.
Well, the Xenomorph in Alien 3 didn't attack Ripley because she was carrying a Queen embryo, not so sure if it would refuse to attack humans with regular xenos, thought it would probably be reluctant.
Dragon Ball features sci-fi tech, so I pick that universe. Bring Dende, the Dragon Balls, Z Warriors, watch the carnage. Once the xenos are all gone, wish back everyone killed by them within the past year.
By the end of DBZ, the Dragon could grant two wishes, so you could just wish all the xenos into the corn field, then wish all the humans back to life. Damn, why didn't I think of that?
I'm not so sure if I'd send the Z Warriors down there though. I suppose they're strong enough to just rip a face-hugger off if it somehow gets attached, though the acid might pose a problem. Plus, if one of them somehow does became infected, could Dende actually get rid of the embryo? We know that he can heal injuries, but a parasite is not an injury per-see. The
last thing we'd want to see is a Super-Saiyan-Xenomorph hybrid, and Goku in particular is stupid enough that he may actually get infested.
Though I suppose you could just send Majin Buu as he'd be completely immune to them. Hey, he could also turn all the Xenomorphs into candy!
"I reject your reality and substitute my own!" - The official Troll motto, as stated by Adam Savage