XP Locked out of a "healthy" system

[RussellXPD]

Yes, thanks, Black Viper had some useful hints. I didn't know that using services.msc was safer than msconfig, or why, but I sensed it because I knew that if I copied the settings from a sister computer I would be unlikely to do much harm. And there was the glaring fact that well over half the services had been shut off.

 

Things are working fine now but I'll be keeping a sharp eye out for further trouble.!