Then you download the server application from this site. It currently is only compiled for Windows or Linux. Then you make a donkey.ini according to the documentation . Set the seed server to a working server so others will find you. Next start dserver and your eDonkey2000 server is now running.
Servers take very little bandwidth.
They mainly need processing power. Here are some stats provided by maurice. There is tons of information out on the internet about Divx however.