I use the winows update site regularly, and have all the available updates.

The problems has got slightly better as many of the recent crashes were related to having upgraded McAfee and also having installed a pop-up blocker. I have 'enabled' McAfee in my pop-up blocker which has stopped some of the crashes.

I am still getting occasional crashes however (maybe one time in 6 when shutting down). I'll see how it goes and post further minidumps if it keeps happening.