You are obviously looking for a resource-saving OS. My suggestion is to use the FreeBSD you already tried and fine-tune X-Windows with a window-manager of your choice, but stay away from the "Desktops".

I have to admit that i hate desktops with a passion because all (regardless of being KDE, GNOME or whatever i have come across) are power-hungry monsters which mostly do what their creators suppose to be cool instead of what i want. My system of choice is a native X and mwm (Motif Window Manager) on top. mwm is simple to configure, there is exactly one file: "~/.mwmrc", which contains the main menu, which pops up if you right-click into the root window. IMHO this is all the GUI one needs. I despise all the toolbars, icons and whatnot, which is just cluttering my valuable monitor area.

If you want a window manager with a little more functionality you might consider "fvwm", but you will have to (re-)write a 50kbyte-config-file and i never bothered to learn the myriads of keywords and what irrelevant behavior they control. Still, fvwm has a very small footprint compared to monsters like compiz and the like. Yes, it (like mwm too) can't create half-transparent octagonal terminal windows which wobble if you touch them with the mouse and have a 3-D image in true-colour as background, but, honestly, my work as sysadmin has rarely suffered from this shortcoming. An xterm with a solid background and a well readable font in one colour is perfectly enough for my simple taste.

I hope this helps.

bakunin