If you have authorization or if your dvds are not legaly protected that you can try to import the vob files into adobe premiere by changing the vob extension into mpg and then convert it to iphone, check the box that says "device central" or something like that and a window will pop up in your screen with some iphones models so you can watch your footage .
ps : This was just a brief, it's a litle more that this but if you already know premiere you'll get there easly.
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