I'm picking up a couple of complete games this week. It is going to be between 25 - 10 degrees everyday. If I leave them unplugged and let them warm up before I plug them in, will the cold break anything?
Not much you can do. These games are stored in cold warehouses and fire right up 10 years later. Really, I remember selling a Pac Man in 10 degree weather (or colder) a couple of years ago and unplugged the PCB and left the game ON to keep the chassis warm. The large caps are what I'm worried about.