Most of the DVD's you backup (about 99%) will only require the use of DVDShrink and AnyDVD, and can be backed up in about 15-25 minutes. For the more difficult DVD's you can use DVDFab Decrypter or DVDdecrypter first to copy and decrypt the DVD to your hard drive, then you can use DVDShrink on the files that were copied to your hard drive.

Note: DVDShrink and DVDdecrypter are no longer being supported by their authors and may have problems with some of the newer DVDs (encryption). My recommendation is to use AnyDVD along with DVDShrink (AnyDVD runs in the background and decrypts DVDs on the fly). Although AnyDVD is not free, it does work very well and you will get lifetime updates with the purchase. If you don't want to spend any money on AnyDVD, you can use a two-step process that is totaly free, and will decrypt most of the newer movies. Just use the DVDFab Decrypter Guide below.

Step-by-step Guides:
DVDShrink Guide: Backing up a retail movie (DVD-9) to 4.7gig (DVD-5) DVD media.

DVDFab Decrypter Guide: Copies a DVD to your hard drive and decrypts it (use this guide if you have problems backing up your movie with DVDShrink). This program is probably easier to use than DVDdecrypter, and does a pretty good job on scratched DVDs. If you have problems backing up newer movies, make sure you download the latest version of DVDFab Decrypter...bookmark their site, you may be updating it every couple of months.

DVDdecrypter Guide: Creating an ISO image of a retail movie (use this guide if you have problems backing up your movie with DVDShrink).

Software used in the guides above (the first three programs on the list are free to download and use):
DVDShrink 3.2.0.15
DVDFab Decryter
DVDdecrypter 3.5.4.0
Nero 6.6 (recently updated to 7.0)

My setup (your results may vary):
Operating systems - Windows 2000 Pro and Windows XP
DVD burners - NEC 3500a and NEC 3540a
CPU - AMD 2400
RAM - 512 Megs