Ignition switch will not turn into the lock position

When I bought the car the owner told me that I have to put the parking brake on to keep it from rolling. Well after looking the car over and doing some research I realized that the ignition switch does not turn all the way to the locking position. I tried to wiggle it and also noticed that if you turn it off and back on you have to pull the key out and put it back in. To make it turn over. Plus I can pull the key out in any position. It does not lock into the ignition switch. I am hoping that I can fix the switch and it not be the interlock shifter or trans-axle.