I think both workout styles would work for fat loss. Like the other members said, it's not so much about what type of workout as the consistency of it. Once you are in a regular routine of working out around 5 days a week you can try all different kinds of workouts to see how your body responds. HIIT training is definitely awesome for fat loss, but weights are also good because the more lean muscle you have the higher your metabolic rate will be.
Definitely watch your diet too. Eat 5-6 small meals a day and make sure you are eating lean protein with each meal in order to feel full longer and feed the muscles you are creating. I would even suggest a high quality protein supplement after your workout. It's a fail safe way of giving your body the nutrition it needs after exercising.
One of the biggest keys is not to overdo it at the beginning. Start slow and steady and keep challenging yourself as your fitness and strength increase.