My parents and I are going to Greece and other balkan peninsula countries in Spring of 2016 and would like to see Greece for a week and perhaps Athens(sorry just not really interested). If we did see Athens, what good greek ruins are there besides the parthenon and agora. We also want to see some other ruin towns, like Delphi, Epidarus, Mycenea, Olympia. Any others you recommend? Also would love to see some islands if possible, which ones are the prettiest? Thanks!! What towns and Islands do you recommend?
With just one week, you can see the Peloponnese (Olympia, Mycenea, Epidavros and Nafplio) and have time for either Athens or Delphi. How are you travelling from the other Balkan countries? Unless by car (and that might come with logistical issues), you will have to fly into Athens so might as well spend a day or two seeing some of the greatest ancient ruins in the world. Plus they have a very good archeological museum. If you prefer islands, you'll spend your week doing that with perhaps a day or two for Athens and maybe Delphi. If wanting to see the Peloponnese, you'll need a car.
You have plenty of time to do some research and figure out what you really want to do and see. I do recommend getting some guidebooks and explore online to help you narrow your options.
If you fly in and out of Athens (the largest airport in the Balkans, unless you go to Istanbul), I strongly suggest you spend at least 2 nights before the flight back. If you are in the islands sometimes you get stuck because of weather related events. So you will have at least a full day (and two evenings) to see Athens. You can't go to Greece and not see the Acropolis, the Agora, and spend the evenings at a restaurant in the Plaka.
Douglas and Roberto made important points about transportation issues; flying is usually the only practical connection to Croatia, for instance; see also http://www.ricksteves.com/travel-tips/transportation/trains/greece-rail-passes. If Athens and the Peloponnese is your focus, Rick's guidebook covers that area well. In addition to the ruins, a couple of archeology museums can really help complete that experience, with art and artifacts from the sites. The largest museum in Athens has a great collection, but limited descriptions, so download Rick's free Audio Tours for the Athens sites at http://www.ricksteves.com/europe/greece, under "Listen."