George, Just slow down a bit and get to know the detector. Everybody has most of the same issues as you except the noise cancelling thing you mentioned. There is no machine that just sees desirable targets. Many targets show good when they are trash and that's all there is to it. If you recover 1 good target for every 10 bad ones you're doing good. Don't get discouraged it's a hobby not a sport to get rich with. Take a look at the Minelab 705, Nokta Simplex machine or Minelab Equinox 600. There are many easy to use machines out there new and used. However there is no "best" machine that will find only good things. Learn the machine, research the area to increase your target finds and be patient.
Good luck! John