White Screen Kingdom Heats 2.5 Final Mix

Try launching the KH2 .self file directly using the Boot SELF option and selecting PS3_GAME/USRDIR/kingdom2.self

Also try verifying your disc's integrity

To check if your disc was dumped correctly, you can use PS3-ISO-Rebuilder tool (http://jonnysp.bplaced.net/)
You will need to load a corresponding IRD file, and then your dumped disc folder (JB Folder) or the decrypted ISO.
Wait until all files are checked, everything should be green, counters for missing and corrupted files in the lower left corner should be 0.

I figure out the problem. So Winrar was extracting two same files (kingdom2.mself), Winrar told me " do you want to change your file named kingdom2.mself". I decided to try with 7zip and the problem was that : on 7zip, there was only one kingdom2.mself with a weight of 7 Go. In conclusion Winrar was splitting the file in two and it was impossible to fuse them.
Thanks for the help anyway