Top-left is a bad position for the login form, because it's the very first thing people see. Put your slideshow there, and the login / registration on the right

Top-left is a bad position for the login form, because it's the very first thing people see. Put your slideshow there, and the login / registration on the right. Also, add some graphics. Text-only slideshows do not interest people. It can be simple to illustrate what your do or the benefits you provide using freely-available icons and arrows.