>>719778794 (OP)
The steam version is hd and widescreen but you can also accomplish the same using hacks on an ps2 emulator.
The steam version also sadly ruins the lighting in the game and as such looks signifcantly worse and ruins the look of some scenes entirely.
The only part the steam version is superior to the ps2 version is the fact you it allows you choose what skills demons inherit trough fusion which is very welcome and saves a lot of tedium and reloading saves.
Other than that the ps2 and steam versions are practically identical.