Instructions
Navigate to the Score Hero website and click the "Downloads" link. Download "Guitar Hero Explorer" by clicking the "Download" button. Follow the installation instructions. Download any additional songs on Scorehero that you wish to add to your disc.
Double-click on the "My Computer" icon on your desktop. Right-click in the window and scroll to "New Folder." Name the folder "Custom Guitar Hero 2" or something similar.
Press the "Eject" button on the disc tray and insert your ""Guitar Hero 2"" disc into the PS2. Right-click on the icon of the disc and scroll to "Explore." Press "Control" and "A" on your keyboard to select all the files. Press "Control" and "C" to copy the files.
Double-click on the "Custom Guitar Hero 2" folder. Right-click and scroll to "Paste."
Locate the songs you wish to add to your Guitar Hero game in My Computer. Drag and drop the files of these songs into the custom game folder.
Click the "Eject" button of your disc tray and remove the Guitar Hero disc. Insert a blank DVD-R.
Right-click on the custom folder and scroll to "Burn to Disc." Allow the disc to burn.