I think the cold would slow them down... especially in freezing temps because they could somewhat freeze which slows them down plus slow obviously doesn't work to a zombie's advantage... On top of that what happens in the Summer? The extreme heat speeds up the decomposition process which would make them rot faster so they would basically end up losing their limbs because there would be no muscle to hold them together.
There are many factors that would cut a zombie apocalypse short.
I personally would move somewhere warm, preferably secluded yet in an open area (to see zombies better at a distance) and I would be near water because they would probably sink in water... and clearly obtaining a boat would be a major advantage.
I think that warm climates would be more effective than cold simply because they would tentatively decompose much faster, of course it would smell awful but a rotten smell is much better than being dead.