OK - I see alot of write ups on this topic but most are way old and do not pertain to my issue.
My sytstem was running perfectly until I pulled a bone head stunt. I went to download and install Bit-Torrent software. OK - Now my desktop changed to a warning message about spyware, I can't run the registry editor, I can't run the restore option from msconfig, and so on. I get messages saying I don't have permissions and I'm to see my System Administrator.
My system is not part of a domain, therefore I'm the system administrator.
OK - So I picked up a virus. AVG 8.5 free edition reported 24 different trojans, all with the date time group of when I tried to install Bit-Torrent.
I rebooted, to attempt to go into Safe Mode. Pressing F8 brings up the Safe Mode menu, but when I select the Safe Mode option the system simply reboots and then the computer tries to reboot normally, i.e. not in Safe Mode.\
I let the computer try to boot this way, but all I get is the Windows loading cylon eye, then after a few seconds the screen goes blank, as if the login window would come on next. It never does, and I let it run all night like that. The hard drive lights blinks into a slow rythm. The system hangs on a black window with only the mouse/cursor that seems to be functional.
So my problem is that when I boot into safe mode the computer reboots normally, not in safe mode, then it hangs. When I try to boot normally, the computer does nothing but hangs somewhere along the boot process.
My system has 2-500GB drives (SATA) in it. One has XP Pro SP3, and the other has Vista. I'm currently booting from the Vista side without any problems. I can access the XP disk normally from here, but I don't know what to do. I let AVG from Vista repair the XP disk, and it also found the 24 Trojan issues as did XP.
This is where I'm at currently. While waiting on Experts Exchange, I'm running a full AVG scan on the entire system and all USB and fire wire attached drives.