First things first: PC-BSD is NOT Linux. Both are UNIX-like systems, but PC-BSD is NOT Linux.
The main difference between PC-BSD and FBSD is: PC-BSD is geared towards desktop use; FBSD has been created with server use in mind
- PC-BSD is based on FreeBSD (6.1 currently) and KDE (currently 3.5.5)
- PC-BSD is installed by a nice graphical installer, rather than FreeBSD’s /sbin/sysinstall
- PC-BSD installs a bunch of pre-selected applications (mostly KDE), whereas one has to manually select packages during a FreeBSD installation
- PC-BSD supports all the major package management systems that FreeBSD comes with (PKG, Ports etc) but has additionally the PBI package installer.
- PC-BSD’s kernel has been recompiled with some configuration tweaks to better suit it for desktop use
- PC-BSD comes preconfigured with a number of automatic scripts (i.e. to mount a digital cameral or USB memory stick etc) that only work in KDE. So, if you want Gnome instead of KDE , alas, but for the time being, you will have to install FBSD with Gnome.
So, in summary, there is no real difference between PC-BSD and FreeBSD, except for the and the that come with PC-BSD. PC-BSD is FreeBSD with a nice installer, preconfiguration/kernel tweaks, PBI package management, pre-selected packages and some handy (GUI) utilities to make PC-BSD suitable for desktop use, so the user doesn’t have to worry about configuring his/her system, but rather install it and start working and/or playing.