QUOTE said:
DVD+R DL generally has much better compatibility than DVD-R DL
Wrong!
DVD+R are having less compatiblity when TAO/DAO is used, cause they involve more work from the laser/lens.
When you have some scratch or little errors on your disc, the laser will need more resources to try to read from the disc which leads in the end in hurting your drive much more than if a DVD-R was used.
They still work fine if you set the bookmark to DVD-R (why do you think that every tut is asking you to do so ?).
However back to the topic:
Mario Kart is SL, and playing fine for me on a ... Verbatim Azo DVD+R (my only dvd+r backup ^^).
As far as i know,
DL Games: SSBB
SL Games: All the rest (easy, isn't it?)