However, it is definitely possible to squeeze the contents of a DVD to a CD or to your hard disk in a variety of audio/video formats.
The process involves two steps - first you rip the DVD which essentially means that your software reads (or decodes) the VOB data files on the DVD and stores them on your hard disk. The next step involves encoding or copying back this data back to a CD by compressing it using codecs like MPEG, DivX, etc.
Here are some of the most popular DVD copying programs that are available for free and one of them can even handle the copy protection lock built inside some DVD titles:
DVDx is an opensource tool for converting DVD to AVI, VCD, SVCD, DivX or WMV in one step (including multiplexing, splitting). Simply select the VIDEO_TS folder from the DVD drive and then select the output folder to save the MPG or the AVI files. The MPEG file can later be burned to a VCD using Nero Burning ROM. [read instructions]
Eazy VCD is another free DVD Backup utility that can rip a dvd movie and output it to a CD or as a MPEG files on your hard disk. It creates a bin/cue image of the DVD which can be later burned to a CD-R disk. Support both VCD (MPEG-1) and SVCD (MPEG-2) formats.
While using Nero to burn the CD, make sure you burn as "DISK-AT-ONCE (DAO)" and not "TRACK-AT-ONCE (TAO)" setting.
Simple DivX is another useful DVD ripping software that can help you convert a DVD into DivX or XviD formats using a ssimple wizard-driven approach. Simply select the DVD folder that contains the VOB files and then choose the output destination where the finished movie in DivX format would be stored.
The process can take hours so start it before going to bed the SimpleDivX will shut down the computer on completion.
Here's another tutorial with screenshots on ripping DVDs using a freeware utility called DVD Shrink.
Smartripper is another freeware but forbidden software that can be used to create a copy of a DVD on a hard drive. The program supports three copy modes: Movie (copy the movie only), Files (copy selected files only) and Backup (copy whole disk).
This is a good option if you plan to create an Audio CD from your DVD. Select the AC3 audio stream in the stream processing tab and you're ready to go. [read detailed instructions] Smartripper is able to bypass a few DVD copy protections while creating a clone on your hard disk.
While the above mentioned DVD ripping software will help you convert your DVDs into CDs, the video and sound quality won't be at par with the DVD experience.
If you are planning to split a software DVD (like Windows Vista installer) into multiple CDs, these tricks may not work as the installer is programmed to read files in sequence from a single disk.