That's the bootloader screen and the bootloader is unlocked which can be seen in your pic. If you use the volume up or down button it will give you options to start, power off, restart bootloader, boot into recovery. Hit the power button with "Start" showing at the top right and it should (hopefully) boot up. Look in your app drawer and see if you have a superuser app in there. I've never used a toolkit so can't help you there, I've always used adb.