I've got stainless... I doubt you'll see them inside the fridge, so chrome would be a waste imho. As for the length, that depends on where you plan to mount the taps. If you're mounting in the side, you can probably get away with 4-5". If you're mounting in the door (unelss you want to cut through shevling) you may need a little longer. That decorative wood plate you mentioned would also require a longer shank. ... You should probably just measure the door/wall where you plan to mount the tap and add a half inch or so for comfort.
As for the 12" handle, it will most likely hit if the taps are against the fridge directly. If the faucets are mounted further away (like if you have some sort of decorative plate) they may not. So, there's a couple options.. either go with a shorter handle that won't hit, or get a tap handle angler.