loading game's built in browser fails

how come loading a browser from each game fails and resets?
choosing a 'connect to network'(or something like that)
option in the title result in displaying a message of
'Now Loading' at the right-bottom corner for a half second
and soon reset! (as if cd cover was opened)
This happens only when using backup cds,
while no problem with original GDroms.
(however, 'network competition' works fine in some games)

What's the difference between loading from GDrom and cd?
Could I fix the problem and re-build the fixed iso image to burn?
Or the point is not like that?