Welcome to the forums dillbot.
Avi is just a container, what matters are the codecs used in making the video and audio streams contained within. The most compatible codecs for those dvd players that can handle avi, are divx and xvid video and usually mp3 for the audio. Look through the manual of your player and see what it can accept, then examine the avi files with MediaInfo to see what format your avi files are in.
ImgBurn should be fine for burning avi files as data to your blank dvds.
If you are burning iso files with ImgBurn, post your log from the failed burns here in your thread. You can find the log file by clicking Help within ImgBurn, then Imgburn Logs.