Hardly get spam in my ntlworld inbox, only use that addy for friends and family (must remember to give it to certain people LOL)
Hotmail is my spam receptacle (thanks Bill :p ) and I use mailwasher to sort through that.
As swoop says never open, reply or email them to ask to be removed from the lists as they will know it's a used account and sell the addy to someone else. That way they have complied with you and removed you from their list but you will now be on hundreds more