I hope it's not too late for the answer:
I see a lot of noise in your images. Are they created by Ambient Occlusion, glossy reflections or soft shadows? To speed up the animation you might want to turn off AO, and use sharp shadows and sharp reflections wherever you can. When not possible - one can use lowest sampling rates for soft shadows that does not look grainy (to avoid flickering) - the same goes for AA samples. If you don't need very deep 'tunnel of mirrors' then RayDepth scene attribute set to 3-4 if there are only reflections or 6-7 when there are some refractions will speed up rendering a lot.
As for rendering itself - I can suggest rendering separate frames to *.bmp, at night, using all cores you have/all cores on all computers around
It can be done using several instances of Anim8tor, each having the same scene loaded, but with different range of frames assigned for rendering.