Hi, welcome to these forums
It's your own fault you got the sponsorprogramme, you clearly get the option NOT to install the sponsorprogramme (just choose (I do NOT accept during the install). If you uninstall Plus! you will get rid of the sponsorprogramme without any problems, afterwards you can reinstall Plus! again without the sponsorprogramme.
Also check:
http://shoutbox.menthix.net/showthread.php?tid=21598
Edit: what exactly do you mean about "is being sent to msn"?