Burning as Data will simply create a DVD with your AVI file on it.
It is then up to your DVD player to be able to play this file.
It is likely that the DVD player is at fault, not the burning.
To confirm this, put the DVD-R back into your computer and try opening the AVI in Windows directly from the DVD-R, not the original file and see what happens.
If it plays fine then the DVD Player is the problem and it cannot properly play the AVI.
You will need to convert it to a DVD format and burn this as a proper Video DVD.
I am not sure how this is done in Nero as I haven't used it for many years but I recall it has a function to do this.
I personally use TMPGEnc Video Mastering Works to convert to DVD but this is not a free product.
There are many guides available at VideoHelp.com for AVI to DVD conversion using both free and paid-for tools.
It's just started to happen. A few days ago I burned the same .avi and watched it on the same dvd player (connected to my tv). Yesterday, I started getting this error. Could this be a sign that the PC DVD writer has fault and needs replacement? – JoeM – 2012-02-09T17:10:12.243
as I said, can the pc read the avi off the dvd? – Shevek – 2012-02-09T20:05:43.527
yes it can. it seems that there is a problem if I burn the .avi file which has white spaces in its name. funny... – JoeM – 2012-02-10T11:54:51.577
must be something to do with the media chipset on the DVD player - remember, DVD players don't play AVI by default, they need an extra multimedia chip to do so and they are not all created equal! – Shevek – 2012-02-10T12:00:38.977