I know that you can get solar screens for the windows. They're actually pretty popular here in TX for south facing windows. But they go on the outside of the house and asthetically speaking are quite a bit darker than standard window screens and cover the entire window top to bottom.
There's also a product made by 3M, not sure but I think you have to go through a dealer, I know my parents had it done (in IL) on their sliding deck doors that face west and are in their kitchen. It helped a LOT with heating and sun control. They have wood floors so they also looked at it as an investment in protecting their flooring.
As far as the safety locks there are some that screw onto the frame but don't actually screw into the frame, if you have metal/vinyl windows. I'm pretty sure you can just get them at Home Depot, Lowe's or Menard's. Our neighborhood pool put them in the bathroom windows before they had bars installed on the outside to discourage the trespassers.