I have a oxygen/Mapp gas torch ( i also have propane that can be used insteat of mapp) and need help with it.?

I have had my Torch since Christmas '07 but have never used it because i didn't have the goggles, i also lost the instructions. I just got the right pair of goggles and wanted to start using my torch. I remember that the instructions said something about the length of the flame for different types of jobs, i am looking to use my torch for small welding jobs and cutting thin metal. I am wondering if anyone knew about these torches, and if you do, could you please tell me how long the flame should be for cutting metal, because i cant find alot of information on the internet about these kind of torches.