Okay, a few issues I see with this idea:
1. Porting requires rewriting platform-specific components of the software in question. This generally requires source code (furthermore in OP2 the platform specific bits are not abstracted out to make this easy, even assuming we had source code).
2. OP2 was compiled for Win32 platforms running on x86. You can't just magically "move" code from x86 to MIPS (the platform used in the PS2), emulation is a possibility but the task of writing an emulator to play OP2 successfully on a MIPS platform unmodified would be orders of magnitude more complex than rewriting OP2 itself for MIPS. Again, you need source code for this to be feasible, or if you are going to rewrite OP2, the primary target should be windows on x86.
3. You can't just run homebrew code on an unmodified PS2 (I know, I have a softmodded PS2 and I know people with chipped PS2s), you would need to chip the console (costs money and requires very fine soldering skills) or install a softmod such as FreeMCBoot on the memory card (installing this on an unmodded PS2 requires a specific game, you have to rip the DVD, replace an ELF file on the disc with the installer ELF for the softmod, burn modified ISO to DVD and then use a slide card to swap the original game with the burnt one after the system has booted and authenticated the original PS2DVD).
4. Unless you have RGB component or VGA cables (and a monitor that supports sync on green for the VGA cable to work, I'm not sure that most consumer monitors support sync on green) the highest resolution you are going to get is 480i (NTSC) or 576i (PAL), this would be equivalent to about 1/4 of the resolution that OP2 originally ran at on the PC (640x480 since it forced VGA video mode when using directdraw instead of the GDI renderer). (And yes, you only get 240 lines true vertical res cause in interlaced mode only half of the screen is being painted on each pass).
5. Due to the resolution issue noted above, split screen RTS wouldn't really work very well IMO, and network play is only possible if you have either the PS2 network adapter (for fat PS2s, which isn't sold retail anymore) or a slim PS2 which has the nic integrated into the system. (I have a fat PS2 and the network adapter, only because I wanted to put an HDD in the PS2 to play backups)
6.
Its easy to go TO pc, but 80 times more difficult going back.
It's difficult either way, x86 is a CISC architecture and generally has an OS running on top of it with a certain set of syscalls, MIPS on the PS2 is a RISC architecture which requires calls into the PS2 BIOS to do anything such as graphics rendering. In other words: two completely different instruction set architectures and APIs for the programmer to use.
As I suggested above, if you are going to port OP2 the best idea would be to rewrite the game completely for x86 and a modern OS such as windows or linux, it can be more easily ported to other platforms later if source is available.
Finally, I'm not sure why people continually ask about the source code from dynamix. We aren't going to get it, it probably doesn't even exist anymore. (Dynamix was closed after Sierra acquired it, this means most of the IP that sierra didn't care about was probably destroyed). Furthermore, Dan or any of the other programmers would not have any of the source code (when you work as a software engineer, code you write on company time, is generally company property, you don't get to keep personal copies of it for yourself unless you have permission from the company, and even then it's for work-from-home situations or similar generally; you don't get to continue to possess it after you stop working for said company, the developers most likely signed an NDA regarding these things and I doubt they would want to lose their job or be sued because they violated that NDA).
Please, use search on the forum before bringing up this "source code" thing that has been reiterated hundreds of times again.
