Hi, thanks for your advice, I had actually done what you suggested, but in my sharp dvd player it still doesn't automatically load the menu, it just has the default sharp dvd screen on (the one that is shown when you don't have a dvd in the player), however I have since tried the disc in a Sony DVD player and the menu does automatically load, so I guess the auto loading does works in one of the dvd players at least! Would be nice if it consistently worked though.
Mind you I noticed in the past if I burnt DVDs via means other than DVDSP usually they always worked fine on the Sony DVD player, but often wouldn't work on the Sharp or other DVD players. By the way I burnt to a Sony DVD, which is the media I always use to burn dvds as find them the best, so I doubt it is a problem with the media.