"As for using dill instead of mint .... mint is "traditional" (check the grocery store and see if you find any "dill" jelly). I generally stud my lamb with slivers of garlic, coat it with extra virgin olive oil, then coat it with a sprinkle of rosemary. Sandwiches are always from leftovers - and I always use mint for my tzatziki."
I'd have to disagree...
having been to Greece a number of times
and being part of a Greek family it's just not so.
All the tzatziki I've ever had was made with dill.
Cora making half with dill and half with mint is a great idea.
Figure out the way that YOU like it.