For this particular write-up, we'll be using FreeBSD 5.3 -- the 4.x series might be better for you if you've got old hardware, or if you're setting up a server, but for a workstation, we want the latest and greatest.
So, go get your FreeBSD CD -- ISO images available from ftp://ftp.freebsd.org/pub/FreeBSD/releases/i386/ISO-IMAGES/ -- login as anonymous and use your email address as your password and get the first disk's ISO, burn it and boot from it.
Not much will be different from the Installing_FreeBSD_-_Standard_Installation, but you want to be sure to:
give /usr/home a lot of space -- /home is really a link to /usr/home install the ports collection create a group for your user create a user and place the account in wheel install and configure X test the mouse daemon
Choosing a desktop and booting into it
Here you've got some choices, you can use a heavy desktop like Gnome or KDE -- ideal if you want an environment that's closer to the Microsoft Windows approach to graphical user interfaces, but they can be slower to load and use on slower PCs -- or user a lighter desktop environment like Window Maker, xfce or blackbox, which are less user friendly but much more responsive on machines with limited resources.
Installing common applications
Internet -- browsers, ftp, etc. I like the FireFox browser; Opera's good and Mozilla isn't bad either, but they're both a bit heavy for my AMD Duron laptop. I don't need a whole lot of special stuff in it -- the only real customizations I add are my own bookmarks and some plugins, so I usually install via the pkg_add utility and I usually add the flash plugin while I'm at it:
pkg_add -r firefox flashplugin-firefox
Email Thunderbird is the GUI app of choice for me, or mutt if I want to check my mail from the CLI. If you really want something that's Outlook-esque, check Evolution out. /usr/ports/mail/gmail-notifier/ has something that [gmail] users will want to check out (if you're also a Firefox user, you want to use "make -DWITH_MOZILLA=firefox install clean" to install it).
Productivity applications If all you need is some sort of word processing, consider using an app that does just that -- abiword. If you really will need the full Office-type suite, OpenOffice.org seems to be a bit better than KOffice, although if you're running KDE, KOffice's integration with KDE is not to be discounted. If you get a fair amount of MS Word documents, you may want to look into the antiword port -- it converts .doc files into ASCII text. Xpdf is my PDF reader of choice.
Audio I like XMMS, but amarok is pretty good too. Both are installable from ports. If you install amarok, you want to install via ports instead of pkg_add'ing it since there are some build-time customizations that you may want to look into. If you want to install the Real player, be sure and install it from /usr/ports/multimedia/linux-realplayer/ -- don't even bother trying to download it (BBC or otherwise).