About 3 years ago we went through the Black Forest.
Freiburg is a good base for exploring the Black Forest. We stayed at the Hotel am Rathaus in Freiburg, right on a pedestrian walk - which you actually drive on to get to the hotel, but that's another story.
Exploring the small towns in the Black Forest is fun. There's a little clock museum in Furtwangen that's worth seeing. And a neat waterfall near Triberg.
Be sure to check out the Strausse "restaurants" in the Freiburg area. These are small places allowed to be open for 40 days a year and to seat no more than 40 people. You can get info on them in the tourist information center.