What's the best windows now.

[Fishpart]

Mike, they make bays with double hungs on the sides. I have three no problem. Gives the cat a place to spend the day and watch the world. Insulation will fix the ice issue.

[nightfighter]

Big bay windows need to be supported with aircraft cables. If not, they eventually sag, and the side windows get out of square, which is why they don't operate as they should. Can also support with knees and/or box frame under the window. I have fixed bays without replacing by jacking until plumb and square, then installing the knees under the sill. Measure both diagonals to see if square.