To define button type, you need to select this type, using radiobutton from the window:

     You could see that there are three available types of the button.
First type - "Classic Button" includes all standard Windows ( since Windows 3.x ) button types ( pushbuttons, radiobuttons, checkboxes ).
Second type - "Owner-Drawn Button ( supported by Windows )" includes buttons, which can be easily filled by bitmap, or by icon, and user needs no to write any button drawing blocks - all support for these button types is performed by Windows.
Third type - "Owner-Drawn Button ( XP style )" includes button styles, which appeared since Windows 2000/XP. Using this type, you could place on the button both image and text, and all support for this button performed by Windows. You need only to point onto text string and image handle. The only problem - this type is not available for users of Windows 9x/Me.