Press and hold the ESC button for 5 seconds and You should get a message on the center display.
Not at all advised to run Snow tires only in the front. See this article: http://www.tirerack.com/winter/tech/techpage.jsp?techid=164&Those are going to be the 'everyday' wheels for the car, the OEM wheels are going to get autocross tires in the Spring, and I have a pair of snow tires/wheels to go on the front axle in a few weeks.