Since this concerns an update to AVG I posted this here. Apparently some systems crash when applying the AVG 2011 update 3292. This, supposedly, is the fix: http://www.avg.com/us-en/faq.num-4079#num-4079
That is really scary!!! I stopped using AVG years ago. I think it is a great program but this is scary. I use the bloated Norton 360 and never had these kind of problems, but of course, that doesn't mean I won't in the future.