Welcome to the world of recordable DVDs. Compatibility is a common issue.
A number of factors go into compatibility:
- The type of disc used (e.g. DVD-R, DVD+R)
- The quality/manufacturer of the disc
- The DVD players
- The burner used
- The software used
Of these, the software is the least likely to be the issue. Problems are most common if using low quality media, or if you are using a format that the DVD player doesn't accept.
DVD-R tends to be the most compatible. Some DVD players reject DVD+R by design. However, some burning software can set the booktype on a DVD+R disc to make it look like a DVD-ROM, and these are highly compatible.
Older DVD players are likely to have more trouble reading the discs. Recordable DVDs aren't as reflective as pressed ones.
So the first thing I'd do is try some different discs. I recommend ones made by Taiyo Yuden, which are sold under various brand names. Links to a couple I've had good performance from:
(non-printable)
http://svp.co.uk/products-solo.php?pid=1778
(Printable)
http://svp.co.uk/products-solo.php?pid=1897