This is probably common knowledge to the techies around here, but hopefully someone finds this information useful:
Probably since my first time using a computer I've been frustrated and confused by how Windows explorer windows open (size, position, etc). I never understood why windows opened a certain size or at a certain position on the screen and I've always wished I could change it.
So after 15 years of computing I finally decided to look it up.
When you open a Windows Explorer window, you can re-position it, re-size it, change the size of the left hand "tree" area and right hand content area. When you go to close the window if you hold down the left ALT key while clicking the X, Windows will remember your adjustments and open that window that way from now on.