+1 on silicone spray on the door seals (and other weatherstripping, hood, trunk, and door stops, hoses, etc.--just not belts or controls).
Tell her not to wash the car if it's going to drop below freezing that night. Also tell her that if one side is iced over from freezing rain, the other side probably isn't as bad and she might have better luck getting that door open. And tell her not to try to roll down the windows if they're iced up or she'll break the regulators or tear up the rubber. Make sure she gets a good ice scraper and a snow brush--they do not have to be the same device, but some of the combined units are decent.