as far as I'm aware, boiling your water isn't going to do anything to precipitate out iron. In contrast, it will probably make your problems worse, since you'll be concentrating the iron content through evaporation.
my tap water here is substandard for other reasons, so I've opted to build my water from scratch using RO water & salts. Water & Ice stores here sell RO for .40 / gallon, and the cost of the salts for even moderately hard water are negligible. For less than $9.00 I can custom build all the water (mash, sparge, & top-off) needed for a 10-gallon batch and precisely control the flavor profile (among other things) as well.