In most linux distributions, (free and fee-based), there are two approaches to how the installation is pre-profiled.
One approach - aimed more directly at experienced users - is to install the core kernel and services and then allows the user to select a set of packages (applications) that meet the users'/system's needs. This allows the installer/user to install packages (applications) that are specific and tailored to the work the machine is expected to perform - without loading a bunch of unncessary stuff. These applications can either be Desktop-directed stuff (desktop applications, email readers, browsers, calculators, media vieweres) or they can be Server-directed stuff (email server, SMTP server, HTTP server, time server, FTP server, etc.)
The second approach - which appears to be your predicament - is when the distribution provides a pre-profiled installation that provides a kit of applications that are braodly suited to either Desktop or Server-directed applications. Thus, if you select the Desktop then you get a wide range of desktop tools installed - probably without much decision time involved to root out any fluff. SImilarly for Server apps.
It is rare that a Server-focussed distribution will make any specific kernel or system tuning changes between a Server or Desktop kit. That era is largely gone, however you should ask.
Fundmentally, every mainstream distribution that is a "Desktop" or "Server" distribution is pre-profiling the installed applications to suit a user profile.
What you MUST understand is that once the machine is running, you should be entirely entitled to install anything on that machine whether from the "Server" or "Desktop" application pools. It's quite common to install HTTP and MySQL DBMS server applications on a Desktop installation.
Don't get too hung up on the distribution's packaging profile unless they inform you of specific limitations in performance or LICENSING AND SUPPORT (for fee-based distributions).
Normally, you just install any damned thing you want and get happy.
Enjoy.
D.
D.E.R. Management - IT Project Management Consulting