If you are just starting after a time of being sedentary, try to do 20 to 30 minutes of aerobic excercise at a low intensity heart rate zone at least 3 or 4 times a week. If you feel like doing more, go for it but don't get too carried away the first couple weeks. As you feel better you can increase the intensity and duration. I am a big fan of the book Body For Life by Bill Phillips because it covers the essentials of losing fat and gaining muscle through healthy and simplified eating as well as aerobic and resistance exercise. You need ALL 3 to be at your best and stay at your best. Research, read, ask questions here or at the gym and just keep learning.
As for specific excercises, I didn't even worry about that until recently. I'm down to about 15% body fat and I'm trying to get to 10%. I like the way I look everywhere except I still have a slight spare tire. I have been increasing the amount of core excercises I do each week. However, it still comes down to burning off the fat that is there. If the fat was gone I wouldn't be concerned about my mid section because it would be just fine. I hope that makes sense.
Hi there! We are the same height, but you look a LOT younger than I am. 