The released version of Windows 2000, after many beta cycles and three release candidate cycles was build 2195.2. It was extremely similar to RC 3. You can see this on an install of Windows 2000 server (RTM version). It had been around in many previous incarnations as beloved Windows NT 5.0.

Windows NT 5.0 was an excellent, incredibly stable early version of Windows 2000, a couple of years before marketing pulled the "year" numbering scheme from the consumer Windows and tacked it on to NT. We had this build dropped from the Windows 98 beta time frame. NT 5 was really just NT 4 with many of the bugs fixed, and minor architectural changes built in. It was what I ran for quite a while, before moving back to Windows 95 for device support. Windows 2000 had pieces that were 7 years in the making I heard. From what I can tell it was well worth it. All in all, an excellent OS. I figure if it doesn't flinch at my non-kernel development, it's got to be stable.