Droppics Masonry theme
With the masonry theme the image ration doesn't matter because all images will be placed right after the previous building an image wall. The good part of masonry script is that whatever the screen size you'll always get a wall. Upload images, Droppics will modeling the rest with pleasure.
Here's the Masonry theme demo with 2 sub galleries.
This image has been added in one click :)
This is a custom sized image with a menu link in a lightbox