What is this boiling over you speak of? I bring water,salt,butter to a boil,then add rice,stir once and cover. I let it come back to a boil and immediately reduce heat and simmer for 25 minuets.

Why is your rice boiling over? It only takes seconds to bring it back to a boil,so you don't walk away. You don't stir it or anything after you reduce it to a simmer. Stirring it makes it gummy. After 25 minuets on your lowest setting,just let it sit a few minuets covered and then take the cover off and fluff it with a fork. Mine turns out perfect every time using this method.

I am however talking about white long grain rice. I've used different brands but can't really tell much difference between what I've used.