Of course, the body uses energy even when stationary, and some people, particularly heavier ones, burn more calories than others. But regardless of your particular metabolism, an arduous session on a bike or in the pool will do more for you than hopping on a rowing machine. Ball sports vary. Football requires two-thirds more calories than volleyball, tennis and basketball are equally exhausting, while golf and baseball are hardly more strenuous than walking.
Great short article outlining the various amounts of calories burned from several traditional (and less traditional exercises). Link to full article below.