Sorry, I have to agree with GoTravel about the kids going bonkers on the train. Yes, parents will enjoy watching the scenery and avoiding driving, but the kids will be bored to tears. As for driving "in the snow," it's very unlikely that you'll encounter snow until you're in the very northernmost reaches of your trip, and you'll need a car during your stay in snow country anyway.

Nancy, what about Northern Michigan? I am in the Petoskey area, right on Lake Michigan, and nearby are some lovely towns and 3 or 4 very respectable ski resorts! Petoskey has a Victorian flavor and dresses up for the holiday season, especially downtown. There is a lovely Inn, the Bayview Inn, located on the bay (Little Traverse Bay) and you can get sleigh rides through the village of Bay View, which closes for the winter. You can get more info on petoskey.com, or to check rates at the ski resorts, call 1-800-GO-BOYNE.