No, salt doesn't change any of the other chemistry. It just makes the water feel better, at least for most people, it is a subjective judgement.
When adding salt for feel, you want the salt level to be around 2,000. However, your salt will always start above zero, so it is best to get some salt test strips. You can use my Pool Calculator to figure out how much salt to use given your starting level and the size of the pool.