what does this happen??

i have a script in edit mode. I am running another script on a window, that script issued a enter key or function key,
   if I happend to click on the script in edit mode, the window expands to the entire size of the screen.
  i cant get control of teh edited screen, i.e. to reduce its size. i cant get to the X to close it. the entire top of the edit window is off the screen.
I click the file and then exit to close it. i go and edit it again and it expands to the entire size of the screen.
How to i get out of this and why does it happen?