I have visited Greece many times, you will be just fine. If you are spending time in Athens , you will see that the people are much like anyone else, most speak good English . If you are in rural areas , a lot of folks speak little or no English , so try to learn a few helpful phrases. It is a beautiful country with a fine climate, generally warm, you should not need heavy clothing , but check with your travel agent . If you get a rental car, a lot of places have road signs in both Greek and English, I had no problems at all driving around . Hope I have been of help, enjoy !