The other thing is that the file layout of DVD Video versus DVD Data discs is relevant. Block sizes, IFO/BUP gaps, file placement, etc. are very important with video discs, so much so that many DVD players will refuse to play burned discs if they aren't just right (which is why you can't simply burn the disc as DVD Data). Authoring programs simply create the necessary and compliant files; it's the burning process that does the job of writing those files in a way that's compatible with the DVD Video spec.

Fortunately, ImgBurn takes care of all that for you. It'll take your already authored folders, combine them with your specified DVD-ROM folders, and create a DVD Video disc that's totally compliant and ready to go. (Nero is crap at it, even with DVD-5 discs, mainly because it doesn't do the IFO/BUP gaps and block sizes correctly. You're just as likely to get a coaster with Nero as you will a usable video disc.) Given that, and the points raised by Adywan, you've made the right choice in going with ImgBurn.