Cut into a pipe containing natural gas with a sawzall will create a spark and kaboom, goodbye self, house, family, etc. Update your will before messing with gas piping.
I wouldn't trust the shut off at the gas meter to be a 100% fail safe and effective shut off. With your apparent lack of knowledge about gas piping since you are asking, maybe you should get a plumber/gas fitter to do it.
What type of gas pipe is it? Are all the other valves shut off such as to the furnace and range and water heater?