What I've tried has been taking out enough of the main title vob's to get all the menu's, extra's, etc to fit on the first DVD and putting the rest of the main title on a second (yes the second won't be playable.)

1. Nero generates a "DVD Video files reallocation failed" error message. Continuing on results in one of the .VOB's VTS_02_1.VOB in one case or _04_1 in another test to be slightly modified. And the trailers and stuff didn't play from the menu's anymore.

2. ImgTool classic always generates an 8 gig ISO even when only there are only 4 gig of files present.

I could do just a straight file burn (not video) in Nero but I would like the menu's and extra's to be playable if possible. Another requirement is that I be able to recreate the original dl dvd in case it becomes damaged. So, something like DVDFab which mucks up the menu's wouldn't work.

Any thoughts on how to accomplish this? Sorry for the long post.

I guess ImgTools follows the IFO structure that poiont to a DL type media, so it prepares full 8GB file.

Try using DVD Shrink of the 4.7GB VIDEO_TS folder, Open Files, and Backup. see is you get what you want.

That's fine for creating 1 disc but I don't want to use compression so 2 discs is ok.

Thanks for the suggestion but unfortunately Shrink generates an error because of the missing VOB's and won't go on.

In that case you should look into more advance programs, and try to blank the "missing" VOB as dummy VOBs. For example, on the first original rip, use TitleSetBlanker program to blank the extra VOBs (Of course keep the backup for later). Then use your reduction as you described.
Other wise you need to use even more advance programs like VobBlanker, IFOEdit, etc

This will not be easy to do. In fact, I'd wager it's impossible to keep the menus and stuff without manually reconstructing/re-authoring the whole DVD!