Please note: Lunch is generally served between 12:30 and 2pm, dinner from 7:30 / 8ish until late. Don't expect to get fed at 5pm!
Eating in, you have a well equipped kitchen at your apartment, and fantastic shops selling really fresh fruit, veg, fish and meat all year round. Many of the veg shops grow much of the produce they sell, and most of the rest is from Sardinia.
Excellent wines come from Bosa and Sardinia in general. Bosa is famous for its Malvasia di Bosa, a rich white wine that is very strong. Commercial Malvasia can be a bit like sherry, but Bar Zio Elio make their own (oppostite the Cathedral) and also the vegetable shop on Corso Vitt Emanuele ll. The wine from these people is far better and they will usually let you taste some. Also there are vineyards that sell direct, especially around Modolo and on the coastal road to Porto Alabe.
The local red wine is variable, again the shops mentioned above make their own and it is worth trying. The commercial red wine, Cannonau di Sardegna is strong, dry, spicey and generally good. Monica di Sardegna is a little lighter, but also generally good. Of the commercial white wines the Vermentino is a generally delicious dry white which can be still or sparkling. Vermentino di Gallura is a particularly good DOC. Vernaccia is a strong sweeter white from near Oristano that can be a bit like sherry. There are many other lesser known whites produced all over Sardinia, with some excellent fizzy ones. Of particular note is the Torbato Brut from Sella & Mosca, and the wines from Santa Maria La Palma both near Alghero. You can also visit their vineyards and sample their excellent wines. The shop 'Veritas' sells a range of local and other wines and also do their own wines on tap. They are down by the old bridge next to Bar Zio Tore.