OBDSim on Windows
OBDSim works great on Windows. The short version of how to use it is:
1) Download and extract the latest build
You can browse here, or the latest should always be here: obdsimwindows-latest.zip.
2) Download and install com0com
In com0com, I leave CNCA0 as-is, and usually chance CNCB0 to a regular com port name that's not in use - eg, COM4
3) Double click obdsim.exe to launch it.
More detailed instructions are in the download file, the files included are also available in the source, or online:
obdsim.txt, the manpage