Best OBD2 Software?

I just picked up a laptop with an eye towards fiddling around with OBD2, can anyone recommend an OBD2 software package for the vx? I've looked at a couple websites and it sounds like there is both a standard OBD2 baseline and then vendor-specific stuff in addition. I've seen software that knows the special stuff for BMW and Audi and the LS1.

It looks like Isuzu uses the GM version of the OBD2 protocol, does anyone know if that means Isuzu also uses some/all of GM's vendor specific stuff too?

try this
http://www.troublecodes.net/technical/scaninfo.shtml