I don't know what daikon greens taste like, but a good use for a large amount of greens is to cook them down and use them as part of a filling for a tart, maybe with some ricotta cheese and any other ingredients that would pair well.

You could treat them like collards or chard and saute them with garlic. There are lots of recipes for greens here on the site. (It was the subject of a contest last year.) Here's a recipe from 101cookbooks: http://www.101cookbooks.com/archives/garlicky-greens-recipe.html
and if you want to search this site for greens, here's the link:
http://www.food52.com/recipes/search?recipe_search=greens