Get 245/45/17's up front and 275/40/17's out back. They will fit the wheels perfectly and both be the same overall diameter as stock. Don't let anyone tell you different, I work in a tire store and know how those tires fit on those size wheels.....if you want it to look perfect and not have your speedo out, that's definitly what I recommend.
EDIT: You might have very slight rubbing issues in the front. If you don't want any rubbing at all, then 235/45/17 for the front. It'll make it slightly narrower and slightly shorter.