My W2000 Profess PC had the exact same problem of no desktop and no taskbar after a small icon appeared and disappeared in top left corner-- only had the background picture. I was able to delete explorer.exe in the WINNT\system32 directory through the Task Manager, but only if I did not open the desktop through the Task Manager. If I hit the New Task button in Task Manager to browse my directories, the desktop appeared, and presumable, that prevented me from deleting the file since it "was in use". I deleted the explorer.exe by Ctrl+Alt+Del to open Task Manager and hitting the Browse button (and not New Task). This allowed me to browse to the file without opening the desktop, right-click and delete the file. Restarted and the PC works fine now. Also, I did this after booting to Safe Mode (F8) with Command Prompt, but that might not have been neccessary (I'm not sure), as long as the Browse button in Task Manager was used (to prevent desktop from opening). 'Hope this helps someone, as this forum pointed me in the right direction.