I have found a few more "quirks" with various videos in my PAL VHS collection. Here are the old and new ones along with a few screenshots to show what I have found.

1 Wrong audio

The 1987, 1988 and 1989 Fullscreen versions of ANH do not have the Threepio tractor beam line so therefore do not have the recognised 1985 Ben Burtt remix sound track.

2 No Fox Fanfare

This has been known for a while but the 1995 THX "Last time only" versions of ESB and ROTJ (both Full and Widescreen) do not have the Fox Fanfare.

They go from this...

to this...

missing out this on ESB...

and this on ROTJ.

However, I have just realised that the 1987 re-release of ANH does something similar.

It goes from this...

to this...

missing out this.

Finally

3 Interupted Fox fanfare

On the initial 1982 Fullscreen ANH, as the Fox Fanfare is playing, an announcer talks over the Fanfare as follows "20th Century Fox Video presents."

EDIT

4 Another odd thing I have found is that the 1995 ANH Fullscreen release Fox Logo has changed from the slanting 0 to the upright 0 like this...

The weird thing is that ALL the Widescreen PAL ANH releases also have the original slanting 0, even the 1995 THX Last time only and 1995 Executor box set. It just goes to show the inconsistency in the release of Star Wars films on video in the UK.