open messenger, click contacts, than manage contact, than delete contact. it will bring up the party in your contact list and you can remove them... I understand how you feel... because I don't use it either but our email is built around it.
I have windows messenger on my laptop and it's driving me nuts. I never use it and I can't remove it, and email@example.com keeps trying to log in, even though I have no such address. I tried to remove it as a component, but it's still there. How can I get rid of it?