Kartli is a large region in central Georgia.
Outside of Tbilisi and Mtskheta, you should not expect to encounter anyone who speaks any European languages. Georgian is the principal language throughout most of Kartli, but there is a significant section of southern Kvemo Kartli (around Gardabani), where most residents are Azeri speakers and you may be able to communicate effectively with knowledge of Turkish. In South Ossetia, you should actually avoid speaking Georgian because of the intense ethnic conflict between the Georgians and the Ossetes, who speak Ossetian, in addition to Georgian and Russian. Speaking Russian is only useful and recommended in areas where ethnic minorities live. Among the ethnic minorities Russian is the regional lingua franca and is spoken by many older people, and also by many taxi drivers. The younger generation is increasingly speaking English due to hostility towards Russia, and also because English is taught in schools since independence and has replaced Russian as a second language in schools nation-wide. When in need for help, look for younger people, as they are more likely to know some English.
Find your Marshutka next to the Samgori metro station. They leave to major destinations around Kvemo Kartli (Dmanisi, Bolnisi, Kazreti, Marneuli) and shouldn't cost more than 5 Gel in one direction. Pay the driver at the end of the ride.
SHIDA KARTLI (Gori,Uplistsikhe , etc)
Most Marshutkas leave from the front of Dedube metro station. Expect to pay up to 7 Gel for a Marshutka (depending on distance) or 5-10 Gel for a shared taxi.
Dmanisi Excavation and Museum site: The site where Archaeologists found the "oldest European" and a former cave settlement of early man. Take a Marshutka from outside of Samgori station toward Dmanisi. After about 1.5 hours get out at the Y-junction going up the hill and walk 20 minutes up the road to your left. It will be on your right hand side. If in doubt, try asking the driver for "patara dmanisi iglesia" he should be able to figure it out.
Sulguni- Smoked Georgian cheese. Usually looks like braids of hair.
Koobdari- Similar to Khatchapuri (and traditionally a Svan dish) a disc loaf of bread filled with pork and relatively spicy.
Lobeiani- a disc of bread filled with beans and spices.
Borsch- a mix of potato, cabbage, beet, carrots, and spices. Seems to be abundant in this region than other parts of Georgia
Standard Georgian Beers found throughout the region. Usually 1.5 Gel/.5 litre in a bar or 5 Gel/2.5 litres in a shop. Mtieli is (arguably) the smoothest and most flavorful.