I've seen a lot of questions posted on other forums but have no need to register with them (AF rocks!). Here's the solution for those that have lengthy load time prior to login screen and have AVG installed >>> http://www.youtube.com/watch?v=MhvIw67gWsQ
Why would you install AVG just to dissable it, and why would you make a 6-minute long youtube video to show a two step process?
AVG servers are sometimes very overloaded.. it's better to set it to manual update (under your control) than to allow it to update automatically.. which is why it's causing this boot bottleneck. Also if it's set to do a daily scan and you haven't been up and running at the specified time it will run on startup.. after updating.. and again cause a serious bottleneck and slow boot times.