I acquired an Archos700 about a month back and have been on the journey to figure out how to load DVD video. I came across an article on a website called Ask Dave Taylor which specifically addresses this subject. Link here:http://www.askdavetaylor.com/how_do_i_copy...chos_av700.html
The two software products he recommends - - AnyDVD and CloneDVDMobile - - both work well (cost about $50 or so for pair). These are supplied by Slysoft at www. slysloft.com.
I have moved a bunch of TV episodes with no problem and have been enjoying these on my treadmill and airplane flights. However as I scanned various forums (this one, CDFreaks, and even comments under Dave Taylor's article), there is a problem with longer movies. I used the two programs above to move The Bourne Identity today and the .avi file was about 1.3GB and indicated 1 hr 58 mins duration. When copied to the Archos700 (do this as a USB Drive), the file info will also show same length and duration, but when started in Video Player, it shows length as 1hr 37 mins - - the remainder is ignored. I think this may coincide with hitting a 1GB barrier or something which Archos will need to address.
For recording with the Archos700 directly from a video source using composite video, there is a 2GB file size limit because of FAT32 operating system - - but Archos700 is smart enough to close the first file and start a second one and so on.
Back on the DVD subject, there is a workaround available in CloneDVDMobile where you can cut down the number of chapters grabbed (I think it is on 3rd screen and shows scissors on bottom of preview window) so that you can grab the first set of chapters and convert and then grab remaining chapters and convert. Hopefully Archos will step in to figure it out soon. Everybody should start asking them to fix this -- I sent an email earlier today and will see if they respond.
With regards to two other forms of video movement that I would like -- DV video from a camcorder and MPEG2 video captured with a TV capture card, I am still on the journey to perfect this. The Archos is very fussy about the format of the .avi file - - video is MPEG4 (comes from an XVid or DivX converter) and audio is MP3 which is lower quality than some other forms. I am in process of trying AutoGordianKnot, IMTooMPEG4 encoder, and AllokMPEG4 Converter.