For our honeymoon we went to Koh Chang for the beach part of the trip. We went in December and it was fantastic! I just checked the weather from March 2006 and it sprinkled 6 days and rained one, thats not too bad! We stayed at barali and loved it. Our bungalow was right on the water and it was about $100 US a night. Many times we were on the beach and didnt see another person in either direction! That was the best part. It also isnt a real touristy kind of place so there isnt a bunch of people around. Not sure if you would want that or not??? We went diving and on an elephant trek also while we were there. Good luck on your decision!
Jeffrey and April