By default, salt is kosher unless something is added to it to make it not kosher - usually flavourings. Kosher salt may or may not be iodized, you'd have to check the label on the package to be sure.
No. Quick salt is another name for saltpeter, or potassium nitrate: among other things, it's used for making cured meats like salami. Kosher salt is made of sodium chloride like regular table salt,...