Hi Mike,
Prevent Windows Messenger from Running on a Windows XP-Based Computer
http://support.microsoft.com/?kbid=302089
Disable/Remove Windows Messenger:
http://www.dougknox.com/xp/utils/xp_mess_disable.htm
If you prefer to remove Windows Messenger manually, click Start, Run and enter the following command:
RunDll32 advpack.dll,LaunchINFSection %windir%\inf\msmsgs.inf,BLC.Remove
Note: This will cause a long delay when opening Outlook Express if you have the Contacts pane enabled. To prevent this, click Start, Run and enter REGEDIT Go to:
HKEY_LOCAL_MACHINE\Software\Microsoft\Outlook Express
Right click in the right pane and select New, Dword value. Give it the name Hide Messenger Double click this new entry and set the value to 2.