These links may give you one or two ideas for places to visit?
http://www.creteonthe.net/placestovisit-cre.htm
http://www.interkriti.org/visits/gramvousa.html
http://www.chania-holidays.gr/en/chania_&_arround/
http://www.chaniacrete.gr/index.php?option=com_content&task=view&id=55&Itemid=71

Some places to eat are suggested here
http://www.dianas-travel.co.uk/eat.htm
I included this link because I think we ate at the one called Anopoulos O, which was tucked away in a back street. The old building had no roof on, and birds were singing above us - food was great, traditional music playing and had a great atmosphere and felt historic. Very special. Well worth a visit if you can find it!

Best beach : Falasarna; best restaurant : Karnario in the Old Port Tel: (08210) 53366 (all restaurants are subjective of course!); best walk : Samaria Gorge