Whatever you decide on it's worth carrying some basic winter, equipment which in extreme conditions could be considered more important than what vehicle you are in. Decent tyres, fluids to top up with, anti freeze, ice scraper, De-icer, snow shovel and you can even buy lightweight fold away plastic grip tracks to help you out if you can't get moving again after stopping. Don't forget yourselves either, a hot flask of coffee and/or soup and a few snacks incase you have to get off the road for a while in poor conditions. Being prepared and minimising risk to yourselves by keeping an eye on weather and road conditions will keep you safe than choosing between 2 and 4WD.so I want something that can handle the occasional snow storm.
Safe travels and good luck with your search !