Honestly I have never claimed the banner ads appearing on my MSN, but with my new mini netbook (Meu EEE PC 1002HA Chegou!!!), with 10 "screen, each pixel gain is a victory!
Searching the net I found the tip Banner Remover do MSN Messenger which basically consists of installing the application A-Patch.
It is very easy to use. You install, next, next e finish.
"Who does not have MSN cast the first stone!”
Tested and approved! :)
Dude just has this problem who uses MSN.
I suggest a test in Pidgin Portable.
Besides portable as the name says, he does not have advertisements, é free, and unifies in a single program access to gtalk, MSN, jabber, ICQ and others.
Do a test and tells me later.