Question: Isn't that nicely recursive? 

I've got a portable command prompt on my external drive, and it has a nice .bat file to configure some initial settings, but I'd like more! 

Here's what I know how to set from .bat:

* Colors = (color XY) where x and y are hex digits for the predefined colors
* Prompt = (prompt $p$g) sets the prompt to "C:\etc\etc >" the default prompt
* Title = (title "text") sets the window title to "text"
* Screen Size = (mode con: cols=XX lines=YY) sets the columns and lines size of the window
* Path = (SET PATH=%~d0\bin;%PATH%) sets up local path to my tools and appends the computer's path

So that's all great. But there are a few settings I can't seem to set from the bat. Like, how would I set these up wihtout using the Properties dialogue:

* Buffer = not screen size, but the buffer
* Options like quick edit mode and autocomplete
* Popup colors
* Font. And can you use a font on the portable drive, or must it be installed to work?
* Command history options

Answer: 
Regarding auto-completion:

> 
> File and Directory name completion is
>  NOT enabled by default. You can
>  enable or disable file name completion
>  for a particular invocation of CMD.EXE
>  with the /F:ON or /F:OFF switch. You
>  can enable or disable completion for
>  all invocations of CMD.EXE on a
>  machine and/or user logon session by
>  setting either or both of the
>  following REG\_DWORD values in the
>  registry using REGEDT32.EXE:
> 
> 
> 
> ```
> HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\CompletionChar
> HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\PathCompletionChar
> 
>     and/or
> 
> HKEY_CURRENT_USER\Software\Microsoft\Command Processor\CompletionChar
> HKEY_CURRENT_USER\Software\Microsoft\Command Processor\PathCompletionChar
> 
> ```
> 
> with the hex value of a control
>  character to use for a particular
>  function (e.g. 0x4 is Ctrl-D and 0x6
>  is Ctrl-F). The user specific
>  settings take precedence over the
>  machine settings. The command line
>  switches take precedence over the
>  registry settings.
> 
> 
> If completion is enabled with the
>  /F:ON switch, the two control
>  characters used are Ctrl-D for
>  directory name completion and Ctrl-F
>  for file name completion. To disable
>  a particular completion character in
>  the registry, use the value for space
>  (0x20) as it is not a valid control
>  character.
> 
> 
> 

Couldn't find any command history options in there ( cmd /? ), and it looks like the other options you asked about are set exclusively through registry settings.
For true Buffer Size adjustment use DOSKEY /LISTSIZE=size

You can't change colors within the shell anymore since Microsoft took ANSI ESC control out of the command/cmd prompts.