Implementing a SMTP server on a personal computer (windows)
Why go through all the trouble? Sign up for a gmail account and use their SMTP server.
http://lifehacker.com/111166/how-to-use-gmail-as-your-smtp-server
It's likely that even if you setup a local smtp server you won't be able to send mail to any outside email servers. (only local delivery). Outside servers will probably reject your smtp server since you're likely in a block of IPs known to be dynamic i.e. not static / business class. This is a spam prevention mechanism.
I hate to say this, but have you tried using the mailserver that comes with IIS?