Here's a few things I've wondered about with regards to DVDFab's generic XviD encoding feature:

How should I determine the proper resolution dimensions for specific 16:9 widescreen DVD video? I know 640x480 is the suggested resolution for standard 1:33:1 4:3 AR video, but since their are different types of 16:9 widescreen picture dimensions on DVD (1:85:1, 2:35:1, 1:78:1 etc.), how do I know what the best screen size is to use for each type (in order to preserve the original screen ratio)? Hopefully that wasn't too confusingly layed out.

When making DVD backups using the XviD feature I have too ideas in mind: 1. A whole disc of TV episodes, or a three-hour movie (even after menus and extras are eliminated) looks pretty crappy with standard DVD Shrink style compression, and XviD encoding allows me much better video quality, and 2. I always use a fairly large bitrate, and screen size to preserve the best quality possible. That being said, is a 1-pass encode at a high bitrate really any worse than a 2-pass? Is doing another pass when the bitrate is high already really necessary for good quality?

P.S. Here's a couple short general questions. Does DVDFab use an internal codec? If so, which one (I'm assuming some form of XviD)? Also, I noticed something curious. Everything I have read says you need the independent DivX or XviD codecs to play those files in Windows Media Player and other software players. However, I was experiencing problems and uninstalled both codecs, with plans to re-install the most current version. Out of curiousity, I double clicked an XviD avi I had on my desktop, and it played just fine in WMP even though I'm absolutely positive both codecs are currently gone. How can WMP still be playing them, without the codecs installed?

In my experience large screen sizes are an improvement only when watching on a PC or playing from a mobile device to TV. I can't see any improvement on my Archos 504 at anything larger than its native 480x270.

I have had good results using any of the 1.777778 ratio sizes even on 2.35:1 movies. Not perfect but OK. The aspect ratio of the output files seems to be the same (no stretching or squeezing effect).

I do not use 2-pass because of the encoding time. I do use very high bitrate (up to 2500 kb/s) with good results. The key seems to be to keep the bits/pixel number above 5. or .6 (or more).

I would suggest you download and install AVICodec, a free file analyzer. In addition to information about almost any file type, it will list all the codecs installed on your machine--you may find as I did that you have a lot more than you thought (which may be why the files continued to play). Here is the link for the afterdawn download page for AVICodec (there is a link on that page to the codec page if you find you need any).