Basic Border draws a border around the edges of the picture. The Border slider adjusts its width, and the Color control lets you select its color . You can add a drop shadow to it from the Motion tab to dress it up a bit. Basic Border ignores any alpha channels, which means that borders do not appear in cropped images, for example.
Bevel draws a beveled border around the edges of the picture. The Angle control allows you to change the direction of the light that reflects from the bevel. The Bevel Width slider changes the width of the border, the Opacity slider lets you change its opacity, and the Color control lets you change the color of the light that reflects from the border.