I have a bunch of DVDs, single layer, that I want to copy. Is my best process to rip in the DVD in DVD Decrypter using the ISO mode and write using DVD Dycrypter? Is there anything to be gained to rip in file mode and burn in Nero?

I do not plan on doing any editing.

Also, if I rip in file mode does it matter if I limit the file size and let it create 5 files instead of 1 large one?

I would use Decrypter, and then burn with Decrypter.
ISO read, ISO write. Easy as that.

If you have an NTFS file system on your hard drive, let it make one large ISO file. If you have FAT32, enable the MDS split, and let it auto split for you. I would not try to customize the temporary size of the files. (And if you're not sure what NTFS and FAT32 means, ask and I can explain further.)

Just follow this guide, pretty much:
http://www.digitalfaq.com/dvdcopy/dvd5/dvd5.htm





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Yea, I should have just looked at the guide.

Decrypter is creating one large .iso file along with the .mds file.

It's a pretty simple process, as you've said.