I think all the recollections above may be correct. IIRC, the DVD spec allows a disc to override some stored user preferences, skip to main menu (ignoring auto-play intro content) and play main content (skipping the menus), but not all DVD players had those user pref options - earlier models often didn't. That could definitely be annoying because some studios loved to force ads, trailers, warnings, etc to play.

Some DVD players, especially later, off-brand models, would ignore a disc's instruction to override the user preference. I remember the presence of these capabilities being a key feature in forum reviews of DVD players. Back then, the holy grail was an inexpensive player that had quick load and seek times, ignored region codes, respected user preferences and had analog component output (or a good composite/S-Video encoder chip). Based on these detailed user reviews, the community would arrive at a handful of players that were worth getting. These lists would be regularly updated as models would change firmware or chips and be sold under different brand names in different regions.