First, the problem fixed by "smoothrod" in this thread had nothing to do with operating system incompatibility. He was working on one of the early VRSCA ECM releases (from 2001) that didn't display the VIN number so the software didn't recognize the ECM.
Second, there are several that have run the SERT software with VISTA and USB to RS232 conversion hardware (e.g the
Belkin made adapter from Office Depot not the one from Radio Shack). You'll also need to download a VISTA rated device driver from Belkin. The issue with VISTA is that HD and TTS (company the made the SERT) never certified the software to run on VISTA but that doesn't mean it won't. It means that if it doesn't run, your on your own to sort it out and it might require an XP partition.
edit: Mark beat me to it.