Doesn't do much good to have a wrench if you can only pull the wheel off with it. After you got it off, what're you gonna do? Roll it down the road looking for a repair place? BOTH is the correct answer plus JACK. It'll take all three to get you moving again. UNLESS you use the tire pump/gooey stuff smart provides . . . and then you'll have to buy a new tire anyway~!
Oh, a Nealy Repair Kit can be a big help, too.