I am still here--despite some of the companies telling me there was a price increase on Monday with PGT windows, I wasn't rushing the purchase. Thank you very much. Your advice helps a lot.
Now that I have the model selected, I've been going back and forth about single-hung versus double-hung in some windows. I like the idea of getting more breeze in the bigger windows. I have cats so if they start scratching a screen to get to a bug or lizard on the other side, I can open the top window. From reading these boards, I like the idea one person posted--having double-hungs in the room used as an office. That way the top can be open and not blow stacks of paper around. Taking all that into account, that leaves two windows that I might have single-hungs installed. So I guess I may as well go double-hungs all the way around.
Thanks to everyone who has posted on these boards over the years. There is a lot of good information here and it has been a great resource as I researched this project.
So in return, I'll offer a piece of information that might be of interest to some. I've had some of the window companies push me towards single-hungs in some windows. One reason was because of the curtains. They said double-hungs would be a pain to access behind the curtains or shades. As I get the windows installed, I'm planning to get new window treatments to match the new windows. I learned about Top Down/Bottom Up Cordless Cellular Shades from a friend of mine. With these shades, you can open the top of the shade to match opening the top of the window. Or open the bottom and match the opening at the bottom. Or both! And if you have cats or kids, no cords!