Re: (Pmen18)
Technically, the best tire/wheel combo to run in the winter/snow is as small of a wheel as will clear your brakes with the most narrow tire you can get. I think that puts the MkV with a 16" wheels and a 205-55-16 tire.
On my Beetle, I am going with 17x7"wheel and 225-45-17 Nokians. I don't need the all-out snow traction because Metro NYC is usually plowed, so I will see more wet/icy roads than deep snow.
All that being said, if it were me with the MkV, I'd run the stock 17" wheels with a dedicated winter tire.