For the shutdown issue I'd review http://www.aumha.org/articles.htm
The startup issue would have be checking for a disconnected/unused ethernet port or a SHARE to some machine that is offline. Any P2P software muddies the issue and should be ejected as well as knowing every item you find with STARTER which I note at http://reviews.cnet.com/5208-6132-0.html?forumID=32&threadID=1313&start=0 and the machine should be clean from any pests.
Bob
Up till now, this problem only happened occasionally, but the for the past week, my system has stalled everytime I start it up. What happens is that I turn on the computer, and it will load up normally until right before the Windows startup screen shows up. The computer seems to stop loading right after showing all of the hardware listings such as disk drives etc that are present. I always have to reboot the computer and it will bring me to the option menu of starting window normally, in safe mode, step-by-step confirmation and etc. I've ran scandisk and virus scans, but it doesn't correct the problem. Another seemingly related problem is when I shut down the computer, it doesn't end up showing the "Safe to turn off" screen, but it shows a blank screen with a flashing underscore cursor at the top left corner of the screen. If I turn off the computer with this screen, the next time I start my computer, it would say I shut down the computer improperly. But this second problem only happens once in a while. Any idea how to fix these problems?

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