disk drive says open tray everytime i load a game

i have had my xbox 360 flashed yestersay but im not so sure it was done right i was given 4 games with it to test it when i got home 3 of the games are old and one of them is new when i put any of the 3 old ones into my xbox it reads the disk then displays open tray and continues to do so everytime i open and close it.

I put in the new game and that loads and plays perfect what I was hoping was that someone maybe able to answer my questions?

A = if it plays one of the four games was my xbox flashed correctly?

B = I have taken all four disks and put then into my computer drive
the 3 games that dont load correct dont display and files. But the game that load perfect displays two types of folders, when I take and original games and put that into my computer it also displays these two types of folders were the 3 games that dont load burned correctly or has my xbox not been flashed right?

C = can anyone tell me what file type i should be able to see when i put a copied xbox 360 game into my computer drive?