Seek out Osteria (Hosteria) '700. I had one of the best dishes I've eaten in Italy there. It was a risotto with truffle oil topped with goose salami. The restaurant is in three restored rooms of an old villa with decorated ceilings and interesting flooring. Also, don't miss out on torrone.
I was in Cremona for a couple of days 10 years ago. I wish I could remember where we ate, as we had a couple of good meals. I remember having a wonderful lasagna there. Also a plate of culatello. Torrone and mostarda are two of the local products of that area.
Cremona is a very nice city that does not seem to get much tourist traffic. Cremona is the home to at least one Italian food company (Sperlari). There is a wonderful candy/bake shop on the main pedestrian street in Cremona. Look up Cremona in Fred Plotkin's "Italy for the Gourmet Traveler" for more info.
Be sure to visit the violin exhibit within the city hall. Every morning one of the violin curators gives a 5-10 minute mini-recital on one of the vintage violins. There is also a Stradavarius violin museum.