suggest you make the window in different shape. if the windows is 24 x 12, build the wood frame 5 0r 6 inches bigger where connect to the wood frame on dry wall. it have a great 3D look. the windows look much bigger and the basement collect more light.
The water pipe in picture #4 if it is a "cold water pipe"
In my opinon, it is better insulate it before put up the dry wall