To be able to help - You must supply much more info.
What You share is - something is wrong - What's it ?
And that is not easy to figure out.
• Were there any Error messages as - Error -yyy text ?
• What kind of material did You feed iDVD
- Video codec ?
- photo file formats
- audio file formats
• What kind of project are You trying to do ?
- Movies on DVD
- other extra material ?
• Did You try to split the DVD process into two parts (I do)
- encoding (Save as a DiskImage)
- burn step - Disk Util tool or Toast etc
• When did the error message come up
• What brand of DVD did You use
• What type of DVD - DVD+R, DVD-R +/-RW SL or DL
• Burn Speed - did You set it down (I do to x2)
• Free space on Start-up (Mac OS) hard disk (my never go less than 25GB)
You see ?
Yours Bengt W