Front Brakes Locking On After Car Idles.

Check your brake lines. If they are old, they could be deteriorating internally. That will cause blockage and can keep fluid in the wheel cylinders under pressure. This happens a lot on cars with disc brakes and old brake lines. Also check your booster. If your leaking internally or it's connected to something other than vacuum, or it's on it's way out, it could be applying pressure. Disconnect the vacuum line to the booster and see it it still does it.