If winter driving is one of your most important concerns you should get a 4WD vehicle. The Passat is well below average in reliability and with the 4WD system and loaded up with leather/sunroof, stability management, etc, you will be well over $40K.. The Accord is a good car and with snow tires is decent in the winter but is still FWD. The CR-V is not a full time AWD system, it is on demand so that when the front wheels lose traction, the rear wheels engage. The 2005 model also has a stability management system called VSA (Vehicle Stability Assist) which prevents understeer (also called push, when the front end of the vehicle doesn't want to turn on slippery surfaces) and also oversteer (less likely to happen in a CR-V but this is when the back end of the vehicle fishtails) So with the 4WD on demand, the VSA, ABS brakes, and front, side and side curtain airbags, the CR-V is very safe and competent in adverse weather.
However... even though I am the resident Honda freak on this forum, I will admit that the Subaru system, which is true all wheel drive, with all wheels being driven all the time, is the most capable system on the market. (Along with the Audi Quattro, which is obviously at a much higher price point)The Subaru will handle all weather conditions, and the wagon body style is very space efficient. Some people don't think wagons are "cool", but the new generation Outback is a very handsome vehicle IMO. Depending on where you live, there may not be as many Subaru dealers as there would be say Honda, Toyota, etc. (The dealer in my city closed last year)
I'm not sure about cost on the Subaru, a loaded Honda CR-V is $33,500 before freight and taxes, but a well equipped cloth model is $2100 less.
Decide whether you guys prefer a Wagon or an SUV, see which one will handle your special needs better (especially if a wheelchair is ever something you may have to be putting in and taking out of the vehicle.) That would make any traditional 4 door sedan not as good a choice. If you do lean towards the Subaru you could always get the Legacy Wagon, less ground clearance than the Outback but other than that it's pretty much the same car for less money. A bit less "flashy" looking too if you prefer flying under the radar.