You'd be surprised at how many people know English. Places like Istanbul and Cappadocia are very touristic, so a lot of people know English, Italian and some even know Japanese (they get the most tourists from these countries). You could also spend a little more money and join an English tour group, that way you're not alone most of the time. You'd be fine...to be honest, you will probably get some stares, but I can't imagine people would treat you poorly...I saw people of all races there.
Yes, people were courteous to me...and thought I'm Turkish...I get that everywhere though...I don't have a particular look, so when I went to Spain, people thought I was Spanish, Italy..they think I'm Italian, etc. I suppose I can pass for whatever. Italy is a must see - it is amazing there.
