I have got a VTS_01_0.VOB menu file which is 568MB and have managed to get it down to 270MB using this method from a post I saw (I would mention name but cannot find thread anymore)
I just wonder why remuxing of Menu-Vobs is not possible (option greyd out). I just did a movie with a menu vob (vts_01_0.vob) of about 600mb without actually much going on in the menus. Its usually the same: not much motion or change in the menus. So I lodaded the menu vob in ReMpeg and recoded it to about 1/3 of the original size (2000 kbps). The I tried to convince IfoEdit to remux the menu vob and *tata* was finally succesfull:

Renamed the original menu vob (vts_01_0.vob) to unused title vob 2 (vts_02_1.vob) and copied some dummy ifo to vts_02_0.ifo. Then opened this ifo in IfoEdit and pressed Vob-extras and chose only remux and remuxed with the new video stream to vts_02_1.vob. Then renamed it back to vt1_01_0.vob, opened vts_01_0.ifo in IfoEdit and pushed menu extras. Checked everything except "remove angle pointer" but didn't actually unselected anything to strip in the following menus. Then copied the resulting vts_01_0.vob/ifo back and voila done - saved about 400 megs.
my problem is how do I get this new VTS_01_0.VOB file to replace original VTS_01_0.VOB and for it still to work like normal as I cannot get it to work using this guide but I see the idea behind it

I have come so close but not there yet, and just going round in circles now

Has anyone ever made the menu VOB smaller and reinserted it with success?

suggestions welcome