You may want to visit the Belgian city of Bruge while you’re there, it’s a good daytrip from A’dam/Antwerp.
 
Best thing to do in A’dam is get a transit day pass, but most everything is within walking distance

the awesomest and fastest way to get anywhere in Amsterdam is on bike
i loved it
bike rentals are not expensive
if you take a bike tour (i think i did Mike’s bike tours) they give you a discount on rentals) plus you familiarize yourself with their bike lanes – do this on one of your first days in amsterdam and you won’t waste your time waiting for buses or their streetcars