It sounds like he set up priiloader to autoboot into the USB loader GX channel. Turn on your wii from the console and hold the reset button right after. This should take you into a (most likely) white screen with a list of options (system menu, homebrew channel, ect). Use the wii remote and go down to settings. Within this menu, the top option should read "Autoboot:" If the text on the right reads anything other then "System Menu" toggle the option "System Menu" using the directional pad on the wii remote. Make sure you select "Save Settings". If that doesn't do anything, we'll move on.