1) On the columns, that seems to be a carry over from Outlook Express,
where the Outbox, Drafts and Sent Items use one set of column headings
and the Inbox and all user created folders use another set.

2) You are in luck: British English dictionary is built into WLM, but
it's hidden.

For English Spelling variations:

Edit in Notepad  %programfiles%\Windows
Live\Mail\Proof\prf0009\2\spell.ini
and enter desired lang= and change Lex= if needed

lang=1033  ; US
lang=2057  ; UK
lang=4105  ; Canada
lang=3081  ; Australia

Lex=MSSP3EN.LEX     for: US, UK and Canada
Lex=MSSP3ENA.LEX    for: Australia  - file may not be included in WLM.
Copy to
%programfiles%\Windows Live\Mail\Proof\prf0009\2\MSSP3ENA.LEX   from
%programfiles%\Common Files\Microsoft Shared\Proof\MSSP3ENA.LEX or other
source

Tools, Options, Spelling will still show "English (United States)" with
any of the above selected, but it will check with the correct variation.

If you would like the correct variation listed as well as the ability to
switch between variations, do the following:
  - COPY (do not Move or Rename or else WLM will get upset) the folder
       %programfiles%\Windows Live\Mail\Proof\prf0009\2
    to either
       %programfiles%\Windows Live\Mail\Proof\prfxxxx\1
    or
       %userprofile%\Local Settings\Application Data\Microsoft\Windows
Live Mail\Proof\prfxxxx\1
    where xxxx is the lang value in hexadecimal:
    UK=prf0809, Canada=prf1009, Australia=prf0c09
  - Make the appropriate spell.ini changes in the new folder as outlined
above.

Note: if copied to %userprofile% there will be an Uninstall option, but
not at %programfiles%

--

Mike - http://pages.prodigy.net/michael_santovec/techhelp.htm