Dont have to use dreamweaver, but yeah you have to add them as rollover buttons in your website or else they will be just static images. One image on #link { background-picture: url(img/buttonoff.png); } and another on #link a:hover { background-picture: url(img/buttonon.png); }
But there are tons of ways to do this. This is with CSS. You can use javascript, dhtml, jquery, flash ....... endless possiblities.