Check to see if winavi creates any logs Try burning the project (ISO or Video_TS folder) with Imgburn.
Check Winavi's progam flder and see if you can find the log. Thats' the first place to start. Then try and ascertain whether or not the DVD files it created are still on your Hard Drive somewhere. Check the Winavi setup to find out where he put them. Once you found them, try burning with Imgburn. Imgburn is easy to use. You hit one button if the files are ISO, and another if the files are Video_ts folder.