What tool bar or type are you referring to? If that is IE the "customize command bar" link is seen on the right click menu on internet explorer. There you can choose large or small icons to make them appear like push buttons. But that is a limitation when you run your display at higher resolutions since the text on the menu remains the same size.
For Windows Explorer the only options seen for increasing size is on items seen in the window itself. In the view options menu you can choose from thumbnails, Tiles, Icons, List, and Details there. But even those setting see the exact same sized text on items.