It's not all that simple.
If a DVD is bigger than 4,7GB you'll have to use IFOedit.
This is just the ONLY program that will allow you to do anything.
There are a lot of guides on the net, but for IFOedit i suggest doom9 because the creator of IFOedit is there as well. (derrow)
If you want to make a copy, never stream-strip with Smartripper, because IFOedit will crash if you want to create new IFO's
It's easier to use DVDdecrypter in FILE modus. Copy the needed files to you HD, it will apply DE-CSS, so your DVD on HD is not protected anymore.
If the files are too big, you can strip some streams out, leave the menu, languages, subtitles out etc. (read the IFOedit guide)
If you still have a movie which is too big you'll have to re-encode, OR split the DVD over 2 DVD-R's (also in IFOedit)
Sometimes individual problems can appear, for example DVD's with the WarnerBros Logo will not be re-mepegged correctly, because the logo is non-interlaced and the rest of the movie IS interlaced, so rempeg will be confused. There is also a solution for that (strip VOBid's). Another problem is non-linear timeline (Fast&Furious, End of Days)
But again, there is a lot of learning to to with copying DVD's so go to the guides first and prepare yourself for some coasters
We all started somewhere.. and thanks to Derrow we can get there.