encountered same "freez" issues. used xfce, fluxbox, enlightenment, etc., thinking this was a portion of the system freeze. had opera as a browser which "gummed" 'er up real fast: o lord, for the end is nigh!!! then downloaded the new ati graphics driver which requires the fgrlx(?)driver be removed before install of new driver (as of april 16th). well, after removal of old graphic driver, my system has remained rocksteady, obiedient, warm, soft,,,pleasing. time for a cupa tea!
from another newbie, gateway laptop, celeron m 2 gb ram. all the best!