ddiv,
You might want to check out an app called DVDShrink. You can find it doing a google search or the link might even be found on this forum.
It can be used to rip the movie to HD, rip selected chapters or even certain scenes, re-edit movies (e.g. joining the 2-disc LOTR movies into one) and lots of other stuff I haven't tried yet.....and it's free!
It will let you rip pretty much anything you want from a DVD, and because it's very much a GUI based app (unlike IFOEdit) you can see what you're getting. This is the tool I'd recommend for ripping your trailers from DVD.