If you're staying in the Campo De'Fiori area you should stop in at Ruggeri. The meats and cheese selections are outstanding and the quality can't be beat. The staff is professional and serious about their products but very friendly so don't be intimidated. If anything else, just point at your choices and they will take excellent care of you. There is also a useful wine wall and some other small grocery products so you can do one stop shopping for a dinner or picnic. Enjoy - I miss it already!