Studs do nothing for you in snow...the best traction you can get in snow comes from getting as much of the tire profile as you can flat onto the snow. e.g put the widest tire you can on the widest rim you can (large marge's work GREAT for snow riding...most of us up here in AK use snowcats though b/c they're lighter) Tubasti one side of you tires to the rims in 4 little 2-3" bits so they don't spin on the rim. Then drop the tire pressure super low (15 psi tends to do well, depends on the snow though) Have Fun!!
ps... this depends on the bike you are using and the conditions..but remember that snow sticks to a warm bike and doesn't generally stick to a cold bike. If you are getting snow clogging up your drivetrain try running the bike at outside temp. Snow also sticks to grease and lube... often best to run the chain dry.