OMG u got 2 pointy tits on that graph!
MSN messenger is simply uninstalled through the add remove programs!
Windows messenger, the one u'r bitchin about, is a little more tricky! U could find XP antispy and from there uninstall it or do a simple google search and find the following command to perform on the RUN box that sits on your start menu:
Code:
RunDll32 advpack.dll,LaunchINFSection %windir%\inf\msmsgs.inf,BLC.Remove