I'm a huge fan of interval training for losing weight and improving general fitness.
It's more intense than the average workout, but the rewards are amazing and the actual sessions are shorter...Better results in less time - can't beat that!
Doing exercises which focus on your midsection are no more effective for burning fat in that area than any other exercise (a bit of a common misconception). It's all about making sure that more calories are going out (burned with exercise) than going in (the food you eat). Once you have that formula sussed, that midsection will start looking better
Are there any types of physical activity you do really enjoy? I'd say start with things you enjoy to begin with until you get the habit of regular and consistent exercise. Once you've got the habit,k then you can challenge yourself a bit and get out of your comfort zone...Focus on developing the habit for now