In-The-Moment

Visit greece and croatia or montenegro in 12 day iteneray with day 1 and 12 being travel day from Phoenix arizona. Depart August 23rd from Phoenix. 
We need a nice restaurant on day 7 (August 30th) which is our 30th anniversary, need a recovery day on day 8 on a beach somewhere. 
This is for a family of 6. Can stay in villas, houses or hotels.  
We want a private tour of acropolis, and a private tour of other cultural centers in Athens.  
Where should we do the anniversary, and how soon should we set the reservation. 
We want to Spend the money on the adventures, not the hotels, but we would like something nice for August 30th Anniversary night.
How do we get hotel reservations, and what are some options for each day during the stay.