Any water coming in? All foundations crack. . .when they start leaking or moving then it gets kind of messy. Do you have good drainage? If you have french drains around your house, it might be time to dig them up and replace them. . .they get mucked up after a while. If you don't have them, it might be a good time to put them in. Cracks can be repaired as long as there hasn't been any significant movement. . .especially if it's on a mortar joint.