From my health class, personal trainer, and my own research strength training with lead to more weight loss, better definition (muscle weighs more, but looks much better), and better overall health than cardio. My visit with a personal trainer recommended warming up for about 5-10 minutes, I use either an elliptical, a treadmill, or a bike, followed by 30 minutes of stregth training, and finishing with about 30 minutes of cardio.
I myself usually workout for about 2 hours 4-5 days a week, I do the quick warmup, then I use the free gym workout from this site to lift weights (each workout is core plus focus on one area (back, shoulders, arms, legs, etc)), and then I will finish up on whatever cardio machine I like that day for 20-35 minutes.
You can do a similar workout at home starting with body weight activities like pushups, crunches, and squats and moving on to resistance bands or dumbells along with walking, jogging, or jumping rope.
Fat loss goes hand in hand with muscle gains, you can still build up those abs before you get rid of the layer of fat covering them. I have a lot of fat to lose myself, but it takes time and dedication and there is nothing that will speed it up that is healthy. Just know that if you exercise, especially if you focus on building muscle, you will get there, just push yourself without hurting your body in the process :)