Backing Up DVDs, What's the skinny?

[Nephi]

I am considering the purchase of a DVD burner. One of my reasons is that I want to back up my DVDs onto blank DVDs. I have done some work backing up DVDs onto CDs. This involves ripping, encoding (a process that takes 10-12 hours on my 600mghz machine) and burning.

Does DVD backup with a DVD burner involve encoding?
Will it take just as long until I get a faster machine?
What software do I use?

You get the idea. Before I buy this new Plextor drive, I need more info.

Anyone???