which Game sell more copies.(lifetime)

I think MP8 6-7million

LOZ TP 5.5-6.5 million 

Are you counting Gamecube and Wii sales together for Twilight Princess? I think the Wii version might still hit 5 million, but anything more than that is unrealistic.

Mario Party 8 looks like it's going to achieve completely ridiculous amounts of sales, and will no doubt blaze past TP. It might even surpass the best selling Zelda games, but I think the next Mario Party is going to kill its sales pretty quick.

It's the same as last gen: the games that are accessible to the most people sell the best.

TP is already at 5.67 and shouldn't have any trouble making it to at least 7 million due to the upcoming players choice version. It will be the second biggest selling Zelda game of all time.