Food- In Greece, they eat a lot of salad. But don't let this fool you, after the salad you eat almost always some meat, and french fries or rice. Even though, it is a costal country, fish is not a common dish from what I've eaten.
Accommodations – Greece, and especially Athens is full of hotels of all kinds and all standards. So finding a hotel shouldn't be too hard. Greek Hotels use the European star systems. So a three star hotel will look like a three star.
Getting Around- In Greece, like anywhere else, the car is the easiest way to get around. But be careful! Greece has a population of 12M, in Athens 5M reside. Athens being an old city, the streets aren't really large so the traffic is really bad. A brand new metro system was inaugurated a few years ago. It is cheap and clean. If you are staying in Athens, this is the best way to get around.
Things to do- Greece is full of things to do. The main revenue of Greece comes from tourism, so finding things to do when you are new to the place is an easy task. Historical places like the Oracle of Delphi, or the Parthenon are everywhere and they are always fun to visit. A lot of museums were newly created so if you want to stay in the capital, but still learn about Greece, they are a good option. Finally, if you aren't interested in history. Greece is full of beautiful scenery and beaches, while achieving high culinary standards...
Climate- The Climate of Greece is really Mediterranean. It gets really hot and sunny during the summer and mildly cold and cloudy during winter. Greece is quite humid and it rains fairly often during winter.
Dress- If you are going during summer, dressing warmly won't be necessary. Shorts, tee-shirts and flip-flops, will probably a god way to dress. Don't forget your towel!
During winter, dress warmly. A sweater, jacket and umbrella will be necessary. If you are mainly visiting, don't forget sneakers, as you will probably walk a lot.