After you have read my post on minimal install of Debian, you may want something more than the command line, i.e. a minimal desktop. More here
Although there are many, many minimal desktop environments (or simply window managers, etc.), I chose to go with Xfce. It is a good compromise between a desktop environment (DE) and minimal desktop. It is faster than Gnome or KDE and is still a DE. But what do you need to have it installed?