when it says αλευρι on the packet, that means plain unbleached flour. when it says φαρινα it means self-raising flour, and it's usually in a red packet. You'll also see μαλακο which means soft and σκλιρο which means hard. Most of the major supermarkets carry their own brands of flour which are fine. Robin Hood is a great brand of flour for pastry. Other yellow packets are used for making bread but in particular egg type breads like the Easter Tsoureki. Hope this helps
Hmmm, ironically enough I think that actually in Greece it's the other way around!... At least the major brands are definitely so, with the blue bags from Allatini and several others being the normal kind and the red bags (such as Φαριναπ and others) being the self-raising kind. Not sure if this is a "standard" though, especially with supermarket "own" brands.
Hope it helps!