how do you convert files to a "compatable" file for buring to a DVD+R?

I presume you're talking about video, right? Well dvd- & dvd+, it really doesn't matter on which one as far as your question goes b/c the same file format requirement will apply to both. May I suggest you do a net search. A starting point is this one. But there's many more out there if u search for them. Use those magical words in your search like 'convert files for burning to a DVD'. I did a quick search & came up with 203,000 results. Oh I almost forgot, also check out this.