Ok, so after a few days of perusing the internet and this forum, and a little fiddling around of my own, here is a 10-step guide to getting a DVD onto your N800.

1: You will need two pieces of software, both free:
DVD Shrink and N800 Video Converter (referred to here as NVC)

2: once you have downloaded and installed both apps, place the DVD in your drive and open DVD shrink.

3: Click the 'open disk' icon and select your drive. In the audio and video areas on the right de-select any languages you don't speak.

4: Click 'Backup'. In the following windows make sure you tell it to make a folder and files as opposed to burning a disk or an .iso.

5: This will take a while, but once finished it will generate a big folder with a bunch of weird files in it.
There are three kinds of files: "Backup of IFO" files", "DVD info" files and "DVD movie" files. These last files are the only ones we are really interested in. They are your movie files, der. You can close dvd shrink.

6: To make it easy, sort the folder by file type, this way all the DVD movie files are right near one another. You will know them because they are the only ones to generate thumbnails (in Vista at least).

7: Open NVC. Using the 'open' button on the bottom right select the first DVD movie file in the list, and watch it play. If the file does not play, IT's OK! It just means that it is not the file you want. Hit the red button to the left of the faux N800, and pick the next video file. Several of these will be trailers etc, so unless you want them, keep lookig for your movie.

8: Once you select a DVD movie file that is your movie (or at least the first file of your movie) click the 'add' button in NVC. Click 'open' again and look for the next file, numerically, and click it. Unless you have a really short movie this should also be part of the movie. Keep opening movie files and clicking 'add' untill you have gotten the entire movie. For reference, Transformers was 5, and iRobot was 4 for me.

9: Once you have 'add'ed all of your movie files, you can see that in the queue tab in the bottom of NVC, all of your files are listed. You can play around with preferences as far as bit rates etc on your own, but the defaults aren't too bad. Not great mind you, but not bad.

10: Click Start, and wait. You can see the progress of the encode in the 'console' tab in NVC. Once finished, each of the original files will be in your NVC folder on your computer, re-encoded and ready to be moved over to your N800.

These files have played fine in Canola, mplayer as well as the default N800 media player.

Enjoy!

(PS, might be worth a sticky, considering how many people have asked)

My system, for reference: CPU: Q6700@3.2ghz, 4gb ram, 8800GT, MOBO: Asus P5B Deluxe wifi/ap, Windows Vista Ultimate 64-bit.

Just a side-note, if you have any kind of movie editing software, like Windows movie maker (most new machines), Pinnacle, Adobe Premier etc, you can piece them together and encode them as one file as opposed to separate files.

Thanks Modred. This can be a little hard to figure out for a newbie.

Also, another note: if the DVD you own has copy protection, the above method won't work (please correct me if I am wrong). You need to use a program like DVD decryptor first. But if you do this first, then there are other programs instead of using both DVD Shrink and N800 video converter, that can do it in one step (such as autoGk). Seems like for different people, different options work best in converting video.

NP, nosam.
I'll be honest, I don't know much about encryption/decryption, but I would assume that iRobot and/or Transformers would have some kind, right? I ran both of them through the above process, with no issues.
But again, i don't know much about that kind of thing.

More like the wiki!

I've used handbrake to convert a few DVDs, it works great, excellent quality. Maybe somebody should also do a tutorial on using handbrake to convert DVDs in addition to this one.

I tried handbrake, and while it works, doing the same job as DVD shrink, it had trouble with both DVD's listed above, saying they were encrypted. I tried out several DVD-ripping programs like these, and really DVD shrink seemed to have the best GUI, and most reliable file production.

Done, in 'multimedia'

Modred, you are the man!

Hi Modred189 :
I am doing it the same way (DVDShrink & NVC) but sometimes NVC takes the wrong audio. I converted ID4 and the last of the 4 parts had the directors commentary audio track on it. Kinda ruins the movie when watching....

Any idea on a setting in NVC on how to select the right audio track?
I looked around but didn't find anything.

johenkel