Adeline, the thread you have posted in here is 7yrs old and is talking about a dvd decoder----something that allows you to play dvds on the computer.
If you'd like to make backups of your dvds, you should get DVDFab HD Decrypter to decrypt and rip the movie to your hard drive. This is the free section of DVDFab. Be aware that as you use the free section, you will be using up the trial for the main part of the program, but the free part will continue to work even after the trial is finished. http://www.dvdfab.com/free.htm I recommend this program for the decryption and ripping part, since it is still being updated.
Most commercial dvds are too large to fit onto a regular, single layer dvd that you can burn with a dvd drive. You could burn to dual layer disks and get the whole movie. If you do that, use only Verbatim brand dual layer dvds. Burn these dual layer disks at 4x.
But the usual procedure is to reduce the size of the movie so that it fits onto a regular dvd---about 4.3gb. One free program for this is DVDShrink. It is no longer effective as a decryption program for many newer dvds, but can decrypt and rip movies that only have simple CSS encryption. So it is best to try it first---that way you can decrypt, rip and compress the movie to the correct size all in one step. If it cannot handle the encryption...use DVDFab HD Decrypter to get the movie to the hard drive, then open the files with Shrink.
You can download DVDShrink from www.mrbass.org. Read the guides at that site for using Shrink.
To burn to disk you can use any burning program capable of burning dvd-video. One that is often recommended is ImgBurn. It is free to download and use. Look in the ImgBurn forum guides for directions on how to burn dvd-video: http://forum.imgburn.com/index.php?showforum=4
If you want an all-in-one program that can do all these steps, use the trial period of DVDFab and see if it suits you. The main section of the program will only work for 30 days before you have to purchase it, but that should be enough to test.
Burn to good media, like Verbatim 16x, and don't burn at top speed. Use 8x or 12x.