We stayed in Sirmione for a week, the apartments were within a 15-20 min walk of Sirmione Old Town. Which was far enough away from the crowds and close enough to walk to. There are many restaurants within the town, many with excellent food. But if you head towards the new town, there are some excellent restaurants there too.
The apartment itself was lovely and clean, and the staff very friendly and helpful. Generally the place was very quiet, and we always had a space to park the car. One night we had some noisy neighbours, which we could hear through the walls, but it was only the one night and didn't disturb us too much. We were there in September and the weather was lovely and warm, if a little hazy. Sirmione Old Town gets very busy over the weekend, so being able to walk into the town without having to worry about parking was great.