Question about AVAST Modules???

I am running Windows XP PRO SP1. I am also running Microsoft Office 2003. I am using Outlook as email client. When doing a custom install and selecting which modules to install with the information listed above should internet mail be chosen or MS Outlook as I know both deal with email. Everytime I open Outlook the MS Outllook Plugin activates. This is just a configuration question. Any and all help would be appreciated.

The Outlook provider protects full MS Outlook (not Express).
The Internet Mail provider protects a number of other POP/IMAP/SMTP clients (including Outlook Express).