Our winters can be cold, but not quite as bad as New England. I've kept the 0.5L bottled waters in the trunk before and not had a problem. Probably not the best idea; one of these days I will probably go out and find a small swimming pool.

How about leaving room (1/4) in the bottle or container for the ice to expand when frozen?

As far as food, I've used granola bars, Power bars, Clif bars, Jelly Belly "Sport Beans", and that sort of thing.