what winter setup is good for the snow on an 06 g35 coupe? and what size tire is good?

 

There are many, many threads on this. Do a search for winter tires and you can see all the comments people have on different setups. You need to make sure the overall diameter/circumference match what you are taking off so the VDC doesn't freak out. If you change the overall diameter/circumference then you need to keep the ratio front-to-rear somewhere in the range of no more than 5% difference to keep the VDC happy from what I have read. I have used Dunlop WinterSport M3's in the past and was very happy with them.