You
can tell Finder to open a new window in exactly the size you want if you perform the following:
Close all Finder windows
Open a Finder window
Select the item you normally want in the Side BarDO NOT TOUCH ANYTHING ELSE IN THAT WINDOW
HOLD YOUR BREATH UNTIL AFTER THE NEXT STEP!
Adjust the size (height and width) of the window
Double-cilck the little "||" icon at the bottom of the single column dividerIf you have moe then one column showing,
you didn't follow the directions above! 
Close the window
The next time you open a Finder window, it will be exactly hat size in exactly that location...unless you open another one and close the first one before any other one.
