it´s very safe to uninstall the messenger after following steps:
Make a backup copy of your sysoc.inf file from your windows directory
Rename it e.g. sysoc.old
Navigate to C:windows\inf Open sysoc.inf find
msmsgs=msgrocm.dll,OcEntry,msmsgs.inf,hide,7 in the file
and take out the word hide so the line would look like
Close the file and save it.
Now go to the Add and remove programs applet in the control panel
and you will be able to uninstall windows messenger.
Make sure to click on the add remove windows components button.