Customize with mail.oft, normalemail, theme's or styles??

We are working with Outlook 2007 in a TS environment.
I' am trying to customize sending e-mail. I have being searching the whole
day but I' am getting crazy with the possibilities. Can anyone sort me out?

What I want to do:
1. Chance the default type
2. Insert some standard text en logo
3. Create some company lay-out bullet lists (styles)
4.Make this the same for every user.

As so far I found out:
1. There is a mail.oft at \office 2007\templates\1043. Is this the default
layout?
2. In my default template folder there is a Normalemail.dotm. In discussion
groups
I couldn't find a clear answer, is this the place to customize?
3. I can make I theme with the type I want (in
e-mail_messages\options\theme's )
and save it. but how can I set a default theme for every new e-mail (the
personal theme I made is not in the list stationary/theme's in the
options).
4. In e-mail_messages \format\style's I can change the style and make a style
default. What is better to use for setting type Theme's or style's?
5. There is also I Normalemail.dotm in doc&set for every user. Do I have to
change
all of them, can I copy, or can I make them use all the same
Normalemail.dotm.

Manny thanks
Peter