You don’t unfortunately get to dictate where fat is lost at any given time.  You have to focus on whole body training, and over time the fat in all areas of the body will shed away.  To burn fat, you essentially have to burn more calories than you are taking in, it’s a very simple equation really.  You naturally burn a certain amount of calories throughout the day.  But of course, it is rather small and you need exercise.  Both the treadmill and elliptical machines are great machines for burning fat and calories and working out in general.  They provide different approaches, as elliptical trainers and treadmills both have different levels of resistance.  But with elliptical, you spend your time trying to move through different and higher levels of resistance.  With an elliptical, you should work at the highest level of intensity you can stand, and it is actually low in impact on your knees and so on and so forth.  As far as the treadmill goes, there are various factors such as the incline you might be at, the speed you might be at, etc.  There is a huge difference between walking and jogging or jogging and running.  But once you get down to a lower fat percentage, remember that routines might be harder anyway for the simple reason that lower fat levels are more stubborn.  So you may need to step it up.