If you mean having your own server on your own pc or designated server then what you need is apache. Also PHP for PHP pages and for forums and things, you need MySQL (or similar).
beware that ur connection speed will suffer...... and pray to w/e diety u want that u don't get famous, or else u'll be SOOOOO slow on a home connection.
a web server set up on a home server? lol. for anyone in another country your site will crawl for them, downloading files will be tedious and extremely slow (your upload speed would be split between all visitors) so if you have just 5 or 6 people on the site on a 576/256k connection, if 2 or 3 of them were downloading files then they'd get about 10kbs each...