What is the “Z or THX or AC3 or Globe or NB” in the corner mean?
The Z, THX, AC3, Globe and NB symbols are from the groups who actually buy the VHS tapes and encode them to VCD. This is done to distinguish one release from another and usually to give credit in some way to the origination of the rip. The THX and AC3 is done to convince people to buy the movie because dumb will think that’s what the audio quality is. Just ignore them. Sometimes you don’t even notice them after a while until they start crawling all over the screen, I personally hate that.