Johan - I presume you mean you want to "deconstruct" a DVD to get rid of the menus, intro, warnings, etc and just leave the main movie?
This can be done by reauthoring a DVD, but not directly in LMCE. However, ripping directly in LMCE is highly desireable for identification of the disk, and setting of the media library attributes and coverart.
Basically LMCE rips the DVD to a standard ISO file (but calls it .dvd) - I imagine you could do the rip in LMCE and target a share on a remote PC somewhere, which would get you your image and attributes/coverart. Then go to the other PC, rename it to .iso and use a DVD reauthoring program to strip out what you don't want, or even select the "main movie" component and pull it out to an .avi (or similar) file. Then the resulting .iso or .avi(etc) you would rename back to the .dvd file and this would then realign with the database attributes and coverart entries.
If you pull out an .avi(etc) file from the "main movie" component, don't forget to delete the old .iso file and perhaps even clear it out of the LMCE database (it will appear as an item missing from disk - there's a check box to display these).
Also, pulling out to an .avi file gives the advantage that you can also transcode to a more efficient codec which will dramatically save storage space (DVD's use MPEG2 which is very inefficient by today's standards!)