You do not need ISPconfig for what you want to do.
ISPconfig is more a controll panel for server owners who want to sell serverspace (hostingplans) to others.
(With ISPconfig you can setup hostingplans like for $20 you get 20GB of webspace, 100GB of data use, 5 email addresses, ect ect..)
All you really need is a webserver (Apache), and FTP server (so you can upload your pages) and if you make use of a database you will need MySQL.
You can also add things like PHP, BIND, and an email server.
ISPconfig will interface with all the above stuff, but it's an overkill for only one or two websites