[gh0sth@cker]

You should really ask this in the PS2 forum, but I'll take a stab at it.
If the PS2 game hasn't got Libcrypt - then a straight copy is fine, but you will still need a mod chip as Playstation games can't be copied 1:1 as of yet.
If it has Libcrypt - then you'll have to read the subchannel data in addition to having to use a mod chip.

On the fly is an option where if the user wanted to copy the contents of a cd onto blank cd, then the read and write process would happen simultaneously rather than first read to an image file, then burn to disk.
As the read and write happens at the same time, buffer underruns are likely to occur more and this does not help things at all.