The best thing about using Linux is that you have more control over how your files and partitions organised. With your /home folder it is a good idea to have a separate /home partition, this allows re-installation of the Linux operating system and formatting / and re-installing the operating system and you will not disturb the files on your /home folder. /usr could also be put on a separate partition and this will keep everything separate. I have /usr/local and /home on separate partitions and this makes organising re-installation of the operating system very easy. The FreeBSD UNIX OS does this for you when you are at the partitioning stage, it automatically sets partitions for /usr and the / root partition etc, for you. This makes installation very simple. If the FreeBSD ports package is installed then of course you need more space in /usr for that, but FreeBSD or OpenBSD does not take up too much of your hard drive compared to something like Windows 7, unless you installed a complete KDE desktop and OpenOffice. If a simpler Windowmaker desktop is installed and you just use wpa_supplicant for controlling networking, then it will not take up much space at all. There are also ways of doing the partitioning manually on FreeBSD as shown here [https://www.dan.me.uk].