you would need to run a web server. i recommend apache, but its not the easiest to setup and configure. and its usually for unix/linux, but definatly worth the time. if u dont want to do that, of course u can do a ms web server, if ure daring. and have money. there also may be a couple of other options, but in the end, u need to run some type of webserver/ftp server, etc.
I had a few programs that made your your computer accessible from the internet by typing in the ip, and you can make a homepage, and shar files on your comp. But i had alot of trouble getting it setup with my modem and my friends modem.