Any cardio will help increase your cardiovascular endurance and burn fat. But running is the fat burner par exccellance becuse you burn more calories per minute doing it than you do with other forms of cardio exercise, bar cross country skiiing, which is not a choice for this time of year!
What you want is a good weekly routine that has you doing cardio 3 or 4 times, of varied lengths and intensity, and weight training 2 or 3 days. It's the combination of both that will lose the fat and develop a defined, lean body.
Clare