Simple way to backup your own dvd's for free!
I was going to put together a thorough comprehensive guide on how to do it but im too lazy now so ill just give you the basics on how to get started. Follow these instructions and should be up to burning in just a few hours.
First find and download these following programs:

Dvd Decrypter or Image Burn: http://www.imgburn.com/index.php?act=download, http://www.mrbass.org/dvdrip/ Either one of these will work, you only need one.

Dvd Shrink:http://www.mrbass.org/dvdshrink/

and sometimes Dvd FabDecrypter: http://www.free-codecs.com/DVDFab_Decrypter_download.htm

Here are a few tips on burning.
1. Most blank dvd discs are not dual layer like commercial movies so you have to actually "shrink" the movie to fit on the disc.
A good way to tell how large it is, is to stick the movie in your dvd drive and pull up dvd decrypter. If it is 4,700,000,000 or smaller then you dont have to shrink the movie, you can rip it straight to the hard drive. If it is larger than that then you have to shrink it down to fit. Most newer movies are larger than 4.7. They are usually in the 7,000,000,000 to 8,000,000,000 range.

2. Dvd Shrink is very flexible. Once the disc is analyzed you have many options on what to keep or throw away. You can keep the movie only or take out unwanted subtitles or audio tracks.

3. Do deep analysis on dvd shrink if you have the time. It really does help improve the quality.

4. Remember any movie by Sony or has Aarcos protection has to be decrypted by Dvd FabDecrypter first before it can be shrunk down.

5. More expensive blank discs are not necessarily better. Discs comes from different plants in Asia so Sony discs at Best Buy might not be the same quality as Sony discs from Walmart for example. I personally like Verbatim the best but there are some good cheap ones you can find at Frye's on sale.

Burning Steps
1. Stick in dvd into drive and pull up decrypter. If it does not need to be shrunk (4.7 or smaller) then with iso read mode rip dvd to hard drive. If it is larger skip to step 2. Once ripped onto drive then put in blank dvd find the iso image and turn to iso write mode and burn. Its that simple 10-15 minutes later you got yourself a movie!

2. If it needs to be shrunk pull up dvd shrink and with disc image analyze the movie. This step usually takes 1 to 2 minutes. After analyzing then you can analyze the whole disc or edit out the things you dont want. From general experience if the movie is 55% or above then it should be acceptable quality. 80% or above is basically perfect quality. I personally do deep analysis at this point but its not required. After the deep analysis which takes an hour or less usually then it is ready to decrypt.

3. Hit the backup button. At this screen you can choose to burn it with decrypter or nero if you have that.

4. Once the backup process is finished, ( usually an hour or less) then it is ready to be burned onto disc by dvd decrypter.

5. Just stick in blank disc and if it automatically opened decrypter then just click the disc icon and it starts to burn. If you had to manually bring up decrypter then you have to find the iso image manually with iso image write and then click the burn disc icon. Thats it, its very simple once you get it down.

6. The only exception to any of this is if its a sony disc or a disc that protected by Arccos. If shrink is not reading the disc then either it has this protection or the disc is dirty or scratched. So as an extra step before opening up shrink you have to decrypt it with DvdFabDecrypter then open up the files with Dvd Shrink to analyze it. Once analyzed then go back to steps 2-5.

Its basically as simple as that. For more detailed information just search out the how to guides or go to www.videohelp.com for more information.