I found it works best if I log in on the "discussion group" page instead of the main homepage (and select the "remember me" box). From the home page select "discussion groups" link, and there you will see the "log in" window. It always seems to remember me after I log on here.
There is an option, without logging in, to see all the most recent posts from that same discussion group home page- select the recent or new posts link.
I guess I have been pretty fortunate, only had a couple issues with logging on, all in all the site works pretty smooth for me.