I'm having a little trouble with this myself.
I have tried the following:
Super Mario Sunshine
F-Zero GX
Zelda - Wind Waker
I have a PAL Wii setup with component outputting in 480p mode.
All three games are PAL versions. The only one I can get to work in prog. scan correctly is F-Zero - and only if I select "NTSC" in the backup loader launcher.
The only way to get the other two to even display ANYTHING is to reset the Wii in 576i PAL mode...it doesn't matter which option I choose in the backup launcher, PAL, NTSC, PAL60, 480p or Auto, NONE of them work when the Wii is set up to output at 480p (apart from F-Zero as I said above, only if I choose NTSC). Otherwise, the game either freezes on loading or the game loads but I get corrupted output on the screen or can't see anything at all (the TV displays Invalid Scan Freq.)
I have tried holding down B but to no avail when the Wii is in 480p mode. In PAL mode, once I've held B and the game loads, I get the option to choose 50/60Hz modes, but I can't get 480p to work.
Do the PAL versions of these games definitely have 480p support, or was it only for US NTSC versions?
All PAL WII games with 480p support work beautifully...
Can anyone help?
EDIT:
Got it to work by holding down B from the backup launcher the entire time until the game displays - it asks me to save a new slot on the mem. card, however this way...