2015 Lionsgate Blu-ray or 35mm scan for Theatrical Cut

For the Ultimate Edition with the T-1000 searching John's room and the happy future ending, the 2009 Skynet Blu-ray, which is the older pre 2017 transfer, but has DNR.

2015 Lionsgate Blu-ray (missing the Ultimate Edition with the T-1000 searching John's room and the happy future ending, which is on the 2009 Skynet Blu-ray, which is DNRed)

2017 StudioCanal 4K Blu-ray (and subsequent 4Ks) is heavily denoised and smoothened. Alternatively, 35mm scans for the theatrical cut  is also available. For the Ultimate Edition with the T-1000 searching John's room and the happy future ending, the 2009 Skynet Blu-ray, which is the older pre 2017 transfer, but has DNR.

Original Kodak/ORC CDS mix 5.1: likely on the Artisan DVD and other Pioneer Japan DVD.
Original Dolby Stereo SR: USA Widescreen LaserDisc and others.

Differences and review of the mix. There are earlier stereo mixes and many subsequent remixes on DVDs but it is unclear how many of them are really unique.

2017 Blu-Ray (which has the DNRed transfer), the 2009 Skynet Edition Blu-Ray, and the 2000 Ultimate Edition DVD have exclusive extras. The 2003 Extreme Edition DVD has some exclusive easter eggs.