Yes, you can simply drag the QR code away from the screen.
Alternatively, you can add the following to the end of the Photo Wall link: ?qr=0
So if for example, your photo wall link is: app.kululu.me/s/4h9phv, change it to app.kululu.me/s/4h9phv?qr=0. That will make sure to hide the QR code from the screen.