Reproducible on Windows XP SP1.

If one changes the install path to
"C:\Program Files\Python\", the resulting IDLE shortcut
does get pythonw.exe running but fails to produce any
window, even if the OS is restarted after the install.

If one installs to "C:\Python23\" or "C:\Python\", it works.
So I assume it has something to do with whitespace in
the path.

>Please notice that it is strongly recommended to install
>Python in a path without space

Where is it recommended?  The installer should warn the
user.

>one frequently needs to type the path on the command
>line or put it into wrapper scripts; in either case,
>spaces cause problems.

So recommending that the install occur in \Python23\
is fine.  But with ~x notation and quotation marks, there
should be no trouble supporting whitespace on Windows.