For green beans, you can use whatever you call green beans: Runner Beans, Wax Beans, French Beans, Green Beans, etc.
1 1/2 pounds (575g) of green beans should be about 4 cups, topped and tailed. Don't worry about getting it exact; this isn't the kind of recipe where it will matter all that much. 1/4 pound (4 oz / 125g) of Blue Cheese should do the trick. When crumbled, that should give you a cup. For blue cheese, use whichever kind you choose. Don't add salt until you've tasted it after adding the Blue Cheese. It may not want any.