Your problem is probably either dynamic IP, or your server wont allow any incoming traffic except the standard ports (80, and so on)..... If it is the second one, then you will NOT be able to run a server, unless you set up a proxy, that uses a standard port... Some ISP's block incoming traffic so that you cannot run a web server, or mail server, or ftp server, and so on, from your machine...
For the first problem (dynamic IP), there are a TON of them out there, and you can use your own find, but one that I personally like is
http://www.dyndns.org A specific domain name will be set up for you (at no cost, on this site anyhow), on their site, and whenever anyone tries to access that domain address, it will be pointed toward your IP address, even if it changes from time to time... Very similar in a lot of ways to setting up a proxy...
