MMS Settings - see
http://www.filesaveas.com/mms.html
Should help you out
Did you get this phone through Vodafone? Or did you buy it unlocked?
You could always phone Vodafone and ask them - I'm sure they can send the settings down in a message so they auto-setup your phone.
The reason for having to use smtp.vizzavi.net instead of smtp.ntlworld.com is because Vizzavi is (or was) owned by Vodafone and you can only send through NTL's smtp server when using an NTL ip address (which you will not have on your mobile
)