I really advise you to take a look at Mark SissonsSisson and Robb Wolf's websites. This is a very effective and healthy way to lose weight. Also train muscle groups instead of individual muscles.
Cross Fit is an effective way to do this, but make sure to start at a level that suits you and don't overtrain.
Also take a look at the lowest link that I posted. These are simple workouts that you can do at home that don't take longer than 30 minutes. Also they focus on muscle groups and movement patterns instead of hypertrophy. That way your basal metabolism goes up and you use more energy at rest and during nighttime.
Make sure you stay away from sugar, wheat, vegetable oils, trans fats, and high fructose corn syrup, and you should lose weight like a train!