Neil,
I went to Hanioti last June with my girlfriend. Its a nice resort on the eastern coast of the Kassandra peninsula. It centres around a main square where there are numerous shops, bars and restaurants. We found the restaurants to be of a high quality.
The beach is fantastic although it is very fine shingle not white sand as it can look like in pictures. The sea is unbelievably clear and calm.
We found there wasn't a great deal to do during the day but when the beach is as nice as it is and the sun is baking down you don't really want to do much else! Our evenings were generally as lively or as quiet as we liked. There are plenty of bars playing music until the early hours but also much quieter options aswell.
Pefkohori and Polichrono are the two neighbouring resorts and within walking distance (just) if you fancy a change of scenery. A taxi cost us 5 euros.
Hope this helped!
Steve