I also tried to copy & paste explorer as you instructed and was once again unsuccessful. I got a similar message to the one before, "Cannot copy explorer: Access is denied.
In the I386 folder? It wouldn't let you copy that?
Try in Safe Mode and let me know.
Also, please disable SpybotSD's Tea Timer:
http://russelltexas.com/malware/teatimer.htm
Then Reboot and run a HJT scan and post me the log. Linky below:
http://free.antivirus.com/hijackthis/
This is odd - the logs all look normal to me - perhaps I am missing something. Let's see if we can get that explorer.exe copied and then I can try to rule some things out.....
-- Before you posted here, did you attempt any other fixes or post in another forum. I saw that C:\logevent.dll where somebody might instruct you to copy it, so I'm curious.
PP :)