You can build PG based on the source code of the latest release.
Or you can install PG9.2.1 via the installer. All you need do is build it or download it and install.
See:
installer: http://www.enterprisedb.com/products-services-training/pgdownload#windows
sourcecode: http://www.postgresql.org/ftp/source/v9.2.1/
As for the stability, it depends on the real environment. I believe PG can run well on windows environment.