I presume to that u want to rip a DVD and get the same as .avi file.
Do this:
1. Get DVD Decrypter (Freeware)
http://www.dvddecrypter.com/
2. Get autoGk (Full pacakge) (Free)
http://www.autogk.me.uk/modules.php?name=Downloads
3. First use DVD Decrypter to rip the VOB file from your DVD and save them into a folder.
4. Now open up auto GK...and locate the directory where u've saved the .VOB files...and now u have the option to rip to whatever size...since u wanna rip to 1.37 GB (2 CDS) or 700mb ,tick that option....and then change the other settings if u wish..and hit RIP!!
Note the ripping speed depends on the PC speed and it's performance.
Get autoGK only u have a faster computer.
There are many ways to do this, but u wanted freewares