I'm not aware of a 4x4 van, though there must be some.
We have a transit van which we bought 7 years ago now. We inadvertently bought one that was top spec, so has traction control. It's actually brilliant in the snow. Obviously, it wouldn't cope with 2 foot of snow, but I have driven ours in more than 6 inches of snow, untreated roads, and it's fine.
In 2010, when we had our horrendous winter up here, we had a 4x4 and the van. The 4x4 ended up clonking out because its battery couldn't cope with temps of -18 every night. We used the transit for everything- including getting my sister from her house to the hospital when she went into labour! Out of us, and both my sister's families, only the transit of all of our 5 vehicles between the three families got us places.
Beth