Don't listen to Naf. My brother's got a buzz cut, and he said to use a two. Make sure you ALWAYS look before you shave. Look at the number. When school started, he used a really short one because he put it on with out looking at it, and put a bald square in the back of his head. It was so stinking funny..... I was crying..... Anyways, he had to do his whole head that, then he really looked like a red-neck. XD
I think you should get blade number 1. This style leaves the hair tapered short, or semi-short, or medium. Buzz cuts are fashionable with men and boys who want a short, low-maintenance hairstyle, and it is mostly used by soldiers.