Marc,
I like to use picture windows on the upper 3/4 and awning windows below them. Awning windows can be left open in the rain.
You have many options here but it all boils down to how much you want to invest; obviously the more the better.

If you have regular decking there are spaces in between the boards. You need to bug proof them from underneath with screening.

So many ways ...

The Porch Guy

Here is a link that might be useful: My Album

Thanks PG. I do like the look of the awning windows and the fact that they can block the rain if left open when we are not home.

The crank open windows I was trying to describe in my original question are called casement windows I believe. Are these also recommended for sunrooms/porches? I guess a severe storm that is blowing the rain sideways can cause water to get inside through casement windows though. Are casements typically cheaper or more expensive then awning windows?

The other option would be sliding windows although again the protection from rain when we are not home is not there.

Thanks!