About icons on system tray, you can see avast4.ini file settings on my signature. You can remove them all and stay will avast! working ok.
I do not recommend the use of msconfig or you will spoil avast installation.
Are you using AVG free and avast at the same time in XP? They will conflict…

I think the best you can do is download the version 4.5 Beta because it uses a new mail detection that will work automatically. Please, set up your email account just as avast does not exists. It will detect the pop3/smpt/imap ports and scan your messages.

Instructions here: http://forum.avast.com/index.php?board=11;action=display;threadid=8044;start=0 :wink: