http://originaltrilogy.com/topic/Superman-1941/id/15907
The WB transfer may or may not have been done in HD. The anthology versions DVD and BD are identical to the standalone release, but the standalone release fixed a couple of the errors.
There are actually a number of DVDs with PCM tracks but these are generally early on in the format’s lifespan as it was eventually decreed all DVDs would carry Dolby digital. A number of music related DVDs are PCM as well.