I've actually been down this road of trying to find a good way to play Crazy Taxi.
The PC version is garbage. It was covered earlier about the performance hiccups, but worst yet are the controls. The HD re-release of Crazy Taxi doesn't support analog input. It doesn't matter if you use the analog stick, or even a racing wheel... it's all treated like steering with a d-pad. Abysmal.
Emulating the Dreamcast version is tricky. I've never been able to get Crazy Taxi 1 to work on NullDC, only Crazy Taxi 2. The latest version of RetroArch lets you use Reicast, and while I have gotten Crazy Taxi 1 to boot,
emulation leaves something to be desired.
Emulating the Playstation 2 version is decent. PCSX2 seems to handle the game well, but I don't know if it's an emulation bug or what, but the game seems to have a crummy motion blur filter applied to it that isn't in any other version of the game. Also, because it's the PS2, you don't get triggers for acceleration.
Emulating the Gamecube version seems to be perfect. Dolphin emulates it perfectly, you get the standard analog triggers, all of the music and real-world locations are intact, and there's no motion blur filter. If you can emulate this version, this is what you want.
I can't really speak for emulating the arcade version because I've never tried it. Emulating arcade games, especially 3D accelerated arcade games, always seems like a massive headache. As an aside:
The mobile port of Crazy Taxi is surprisingly good. It's not perfect, but you get the original music and the game adapts pretty well to touch/tilt controls.
The Gameboy Advance port was good for a laugh once. I really liked it when it first came out, but there's no sense in bothering with it now.