Ok lets see here, assuming you will have a rental car.
I honestly would check out this Holiday Inn
https://maps.google.com/maps?ie=UTF-8&q=Holiday+Inn+Express+Mishawaka+(South+Bend+Area)&fb=1&gl=us&hq=holiday+inn&hnear=0x88113314890a1573:0xa42d729539512ba0,Mishawaka,+IN&cid=12881987059647047198&ei=KJa0UuDuHI3gsASJuoKQDQ&sqi=2&ved=0CNkBEPwSMAk
It is your basic holiday inn but the location is pretty damn good, especially when you are gonna be stuck in a pretty boring Midwest town. You will be in the middle of the best shopping and restaurants for 100 miles. ND campus is roughly 10 mins to the west as long as the traffic on grape rd isn't too bad. This location will get you to the toll road entrance/exit in about 5 mins. You can get to Elkhart general in 20-25 minutes from there also.
Trying to think of anything else...... You can get to downtown south bend restaurants in about 15 minutes from that location.
I've lived here my entire life, so you can def trust me that there isn't a better location.
If you want a nicer hotel, that's a different story. Let me know and I can recommend something else.