Brakes: Depending on your usage, they might be worn. It might also be that your discs are crystalized and they need to be cut. It might also be that you just have some brake dust accumulated on them. Simply by checking these symptoms could solve the problem.
Tires: Maybe you might need to have your wheels balanced. Maybe your suspension is worn out. Could be a number of things. If your tire pressure is correct and it is definitely not a flat, maybe it could be tie rods. Not sure as to the exact thing. As you can see it can be a number of things. Hopefully though, I've given you some form of direction so that you can narrow it down.