Frame images in a cool patterned frame background

Start by creating a rectangular selection using rectangular marquee tool.

Press Q to enable quick mask. From "Filter" menu select "Pixelate>>Color Halftone". Apply settings as shown.

Press Q again to disable quick mask. Press Ctrl+Shift+I to inverse the selection. Press Delete. Create a new layer and fill it with white color. Double click the layer to open layer style window. Apply settings as shown.

Insert an image of your choice. Move this layer below the frame layer in layer order in layer palette.