You need to do a proper shut down, not just unplug it. No idea why MS would have charged you to do a setup of 10, you don't need to install 8 first, can just install 10 again. You may want to have someone there that knows about computers look at your setup, seems like it's a mess, and it's hard to sort out from the posts. If the battery is not holding a charge, just unplugging it would cause it to shut down due to power loss, which means corrupt system files or a damaged hard drive is possible.