Brakes are locking up

After driving a few miles I start to get a stiff feeling in the brake pedal and a dragging feeling in the brakes. It feels like my calipers are locking up, like if i'm driving with the hand brake put, and then brakes totally lock up. Weird thing is is that if I let the car sit for a while, more than a few hours or so, the car seems to be normal until I drive it again and I get the same problems.

Can anyone help?