Do not use 1/4" pine board beneath the tiles, unless you want to redo the project again in a year.
You need to have a concrete backer board for your tile, and the installation is pretty specific about this. On the main board, use Ctrl F then "tile" and you should be able to find a few posting describing the process. Beyond that, get information from some DIY books and from the professional tile store (not the big box stores) salespeople who have been installing tile for years.
Greenboard is a wet-application drywall.
Wonderboard is a brand name of concrete backerboard.
Another tile backerboard I like is Hardiboard, which I think is easier to work with.
Don't skimp on material prices. There are two differences between a professional job and a homeowner job: (Skill and Experience), and Quality materials.
You are saving money on the labor, but use the good materials or you will do it over again before you wanted to.