Ok, so I have got Mac OS X which is UNIX based software I think. Well, I open up the terminal window and it looks just like a unix shell where I can view my whole hard drive. I use it to telnet into my shell account with my ISP.
Without telneting into another account, How do I set up the smtp server to send mail using mail. And can I receive mail using my ISP's pop mail account without telneting into my account?
If you have qmail or sendmail (or some other MTA) installed, you will be able to send mail from your machine. Note that sendmail does not have to be running as a daemon for you to be able to send outbound mail. To receive POP mail install one of the many pop programs such as getpop3, poptart, etc. Search on http://www.freshmeat.net to find some suitable programs.