Hi changeit and welcome to ImgBurn Forum.
It does seem you want your AVIs to play on any DVD player, so if ithis is really the case, you'll need to convert them. There's lots of freeware and payware encoders. I wouldn't say ConvertXtoDVD is "just the best". You should experiment with some stuff. AVIDemux, DVD Flick (I know you said that you thought it was complicated), SUPER and payware products. This stuff ranges in price from freeware - some of which is very very good - to real high cost encoders (kinda like professional stuff), so pick something that you feel you can work with and suits your budget.
However, if your current player is sufficient for your needs (as you say), then do as LUK says and just keep burning the AVIs onto DVDs and play them thru that. However, you won't be able to play them on any player.
But, in any event, I'm sure you'll be fine with ImgBurn as your burning solution.
Regards