Try the decorating forum as this is more about windows themselves.

We did the DIY window film (Gila) from Home Depot - it has the same rating as professional film and it was easy to apply if you follow the directions exactly. It is more effective than any blinds inside the windows. You can also choose privacy control tints which would be great for a bathroom you could eliminate the blind. Even more effective is an external barrier - we installed an awning as well, you could do an awning or an exterior sunshade blind to better control the heat. If you do the film and an exterior shade or awning you will notice a big difference from the window heat transfer. Unfortunately though, heat still comes in through uninsulated roofs and poorly insulated walls. You can only do so much, I certainly wouldn't spend a lot of money on professional films, which may not have much impact if the heat isn't only coming through the windows.

what is the distance from floor to the very top of the window moulding?

I have inside mount for my casement windows with blinds. You can change out the handles to either one that folds or a smaller one that looks like a T. I don't know if you can use them on all brands of windows so this is probably something you would want to check out if you are interested. If you know your window brand, I'm thinking their web-site will offer several different handle options. Though more than likely you can find them elsewhere, too.