Roryll:
Well if Roryll could talk and be understood:
1. Close down the hanger bay
2. Turn off the gravity
3. Remove the holo-whatever (tractor beam, door leading into space, ect)
4. No zombies.
Like in Alien I believe (or might be aliens 2)
Even if you removed the zombies what would be the point? As it has been stated there are no usable ships, they were intentionally destroyed.