porting ps2 games to dreamcast

[chao2]

How much of the ps2's library of games could be ported to the dreamcast without too much being taken away from the games?( I already know God of War,Shadows of Colossus,and mgs3 are impossible). If there was some source codes were released or cracked would it be possible to port it without too much of the game being redesigned.

[RyoDC]

Depending on the way they was written.
If they was written in some open-source, wide-known to public, and ported to many platforms crossplatform and opensource high-level C or C++ libraries which are agnostic of hardware, well, maybe, answer would be "probably", in terms of time and efforts.

But I really doubt that much that they was written in such a way - probably they were written using the official C++ libraries from the official Playstation SDK. That means, you need to rewrite about the 90% of the code.

Also, porting one software from one platform to another is not a redesigning, this process called an adaption, and most of the time it is performed by the hands of the developers.

I already know God of War,Shadows of Colossus,and mgs3 are impossible

It is possible to port any game from PS2 to DC with some comparable amount of loss and gains. It's all about time that would be spend on the porting, not the possibility.

[Christuserloeser]

How much of the ps2's library of games could be ported to the dreamcast without too much being taken away from the games?( I already know God of War,Shadows of Colossus,and mgs3 are impossible). If there was some source codes were released or cracked would it be possible to port it without too much of the game being redesigned.

Theoretically speaking, I'd say that virtually anything could be ported. Like RyoDC correctly wrote: The issue would be the amount of work involved.
As you already mentioned, many of the later games were tailored to the PS2's hardware to a degree were it would be next to impossible to do the games' original design justice on any platform not vastly superior in every way without spending an eternity on optimizing your port. It would be much MUCH easier to develop a new, possibly superior game from the ground up than port an existing game tailored to a specific hardware with different strengths than your target platform.