A free weight is one that is not attached to a machine, cable, etc. This essentially means barbells and dumbells. These types of weights are more effective for strength gains.
It's possible but unlikely. To use up an important amount of calories(which will help with weight loss) you need to get your heart rate up and keep it up for some time. And weight training just isn't...
Basically you just want to take a 30-60 second break in between sets over 12 reps. But anywhere from 2-10 you should take about a 90 -160 second break depending on how hard you push yourself to get...