Pretty much you need to convert the video files to a MPEG-2 format (that is the standard format for DVD's) and then author them to a DVD using a DVD authoring program.
I use TMPGEnc DVD Source creater to convert the files then TMPGEnc DVD Author to make the menus and burn them.
How many episodes on a DVD depends on how good of an encode you want. For KR & Sentai, I use pretty high encodes, so that fits 3 episodes on a disc. Which means 17 or so DVD's per season.
-RF