Brett wants to set up his own mail server. Leo doesn't recommend it, though. There's a lot of traffic that would have to run through his own computer. Since ISPs don't want customers to become spammers, they frown on such activities. ISPs will often block outbound servers that use port 25. So if he's in earnest, then Leo recommends using the SSL outbound port 465. He should always talk to the ISP before setting up his own mail server, because they could dump him. Another option is to use Google's server: 184.108.40.206.
Leo recommends using Gmail and have it forward his mail for him from his ISP. Let them run the server.