When I turn on my computer it automatically changes it's theme to Windows Classic, then reboots. I don't even have enough time to do anything. what should i do?
When it reboots, does it come up and stay in Windows or does it continuously reboot? If it's stuck in a loop, then it sure sounds like you have a video driver (or possibly card) problem. Uninstall the driver in Safe Mode and try reinstalling it afterward.