Since you are on WELL water, I suggest that you have your water tested. You could do this at Sears or any other water filter sales store.
You should have a water softener installed if you find that you have hard water (a water softener will pay for itself over time). It appears that the brown stain could be iron bacteria and the smell you have is hydrogen sulfide. Even though a water filter will take some iron out, it appears that you may need a seperate iron filter and an additional taste and odor filter.
a good source to view is the kenmorewater.com site. Also SHOP around since the price for these items could really fluctuate depending on who you buy from!