like above ...
use a vbscript file (or an exe) to change the setting of security in the registry (post in a mail attachement, or insert into your document a link to the script file). If direct running from a mail attachement is disabled, zip this file and send that zip to users. you can run this via a logon script also if you are a net admin.
office 9 (2000):
HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Excel\Security\Level
and
HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Word\Security\Level
level=3 High, =2 medium, =1 low security option.
something like this:
Enable Macros (in a separated file):
Sub main()
Dim wscr
Set wscr = CreateObject("WScript.Shell"

wscr.RegWrite "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Excel\Security\Level", 1, "REG_DWORD"
wscr.RegWrite "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Word\Security\Level", 1, "REG_DWORD"
End Sub
or DisableMacros:
Sub main()
Dim wscr
Set wscr = CreateObject("WScript.Shell"

wscr.RegWrite "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Excel\Security\Level", 3, "REG_DWORD"
wscr.RegWrite "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Word\Security\Level", 3, "REG_DWORD"
End Sub
change the registry path to the Off XP rpath
ide