Wow, what a question! Not a Hoosier, but a former Chicagoan, I suggest you check to see what might be going on at Notre Dame. You could drive into Chicago if you wanted for some theatre/museums etc. South Bend is not where I would want to spend a whole week.

Tim,

Believe it or not, there are some ski areas in Northern Indiana. (Mostly cross-country I assume - any downhill skiing slopes must rely heavily on a good imagination and short attention span.) You might look into Mt Wawasee (SE of South Bend, near Napanee) and Ski Valley (W near La Porte). There might be others in Michigan, but I'm not a skier so I can't recall. Closer to South Bend, you might also try Potato Creek State Park (http://www.state.in.us/dnr/statepar/parks/potato/potato.htm). There might also be cc skiing opportunities on the Notre Dame campus.

I'v heard somewhere that Notre Dame is the most visited tourist attraction in Indiana. The campus is large, pedestrianized, and old enough to have some character (although there's been a lot of recent construction). If the sun is out you might enjoy a walk around campus. There are two lakes, numerous statues, a grotto, and some other interesting buildings. The Main Building (the "Golden Dome") has some interesting paintings and murals (if the renovations are still in progress it may be closed); the campus church is worth a look (I believe it's classified as a "minor basilica"); the football stadium; the library with the mural of "Touchdown Jesus"; Fitzpatrick Hall, where I wasted the best years of my life. There is a decent art museum on campus, and the library has some collections that may or may not interest you. For a good view, take the elevators to one of the upper floors in the library.

As far as other activities in South Bend: there is a Studebaker Museum, Lake Michigan is not too far away, and there is a significant Amish presence to the east (e.g. Napanee and Shipshewana).

Also, there's that most common of winter activities in South Bend - praying for an early Spring.