You're living my life now! Your parents are willing to spend a bit more than my sister, but many of the needs are the same. The main question is if they need a low range 4WD for the real tough stuff or if road-only AWD is sufficient.
The Forester has plenty of space for 4 adults and their cargo (a preference in my shopping too). While an Impreza platform, it is a bit larger and much taller. Long items like skis can go on the roof rack. I would recommend a Forester or Outback over a Legacy wagon (except 2.5 GT) because the 2.2 litre is a bit underpowered. Watch that the coolant was treated properly on 1999-2002 models. There is a recall requiring coolant conditioner to prevent head gasket leaks.
If low range 4WD is required, the Cherokee Classic is the best choice. They are relatively inexpensive and the 4.0 litre I6 runs forever. The Nissan Pathfinder is another excellent choice. While pricey, they also last forever. I would also add the Explorer Sport if a 2 door will work. The room is still there.
On snow tires for the Subarus, I am assuming a full snow versus the perfomance winters I use. Life should go about 3 winters assuming 10,000 miles a winter. I don't know that market enough to advise, except to buy quickly. Winter tire selection tends to run out early.
Did a quick search... found something that is extremely rare here... not all SUV's are 4WD! Also, your market is more depressing than mine. Your parent's $10,000 is going to go not much farther than my sister's $6000 or so is going to go here. Such high miles on everything!
