Remove obsolete term + indicate how to find the program (#1626300).

Suggested by Terry J. Reedy.

Doc/distutils/introduction.rst

@@ -84,8 +84,8 @@ terminal::
 
    python setup.py sdist
 
-For Windows, open a command prompt windows ("DOS box") and change the command
-to::
+For Windows, open a command prompt windows (:menuselection:`Start -->
+Accessories`) and change the command to::
 
    setup.py sdist
 

Doc/install/index.rst

@@ -101,8 +101,8 @@ one command from a terminal::
 
    python setup.py install
 
-For Windows, this command should be run from a command prompt windows ("DOS
-box")::
+For Windows, this command should be run from a command prompt window
+(:menuselection:`Start --> Accessories`)::
 
    setup.py install
 
@@ -144,7 +144,7 @@ archive file to :file:`C:\\Temp`, then it would unpack into
 :file:`C:\\Temp\\foo-1.0`; you can use either a archive manipulator with a
 graphical user interface (such as WinZip) or a command-line tool (such as
 :program:`unzip` or :program:`pkunzip`) to unpack the archive.  Then, open a
-command prompt window ("DOS box"), and run::
+command prompt window and run::
 
    cd c:\Temp\foo-1.0
    python setup.py install