Rip each movie to disk. Then have DVD Shrink ReAuthor mode opened. Choose the Vieo_TS folder of each movie. Select both "main movies" and Eliminate the extra sound tracts, directors cut, and anything else not needed. Let Shrink put it all together and compress to fit.
NERO Recode2 "Remake DVD" is really easy to use. I used it several times to place two movies like "Blade 1 & 2 on TO one disc, also to put two side disc like "Sleepers" "A&B" on to a 1 sided 4.7GB DVD-5.;P
i have not tried it,give it a go,and let us know if ye tried it?
and if its any good...........,.........
DvdReMake.
Starting with v 3.0 DvdReMake can be used to merge 2 full dvds (DvdReMake Pro - 4 dvds). This means FULL - keeping original menus, languages, everything.
Procedure is completely automated, you simply import disks you would like to merge, go to "Tools\Merge DVD..." menu and select projects to be merged. As a result you will get a new project. Export it and you have two disks merged to one DVD.
When played this disk will show a start up menu asking what disk you would like to go to; after that selected disk will play as if it is the only one on the DVD. At any time during playback pushing "title menu" on the remote will take you to this start up menu.
http://www.dimadsoft.com/dvdremakepro/ht_merge_full.php