the fact that the light activates when the button is pressed indicates the problem is in the opener itself.
the problem could be a bad relay inside the opener and if this is the case, it is most likely soldered in and not easily replaceable.
the unit also has OPEN and CLOSE limit switches to prevent damage to the door at the travel stops. it is possible the switches have failed and could be replaced.
if the door refuses to close, the close limit may be the problem. if the door refuses to open the OPEN limit may be the problem.
the unit should also have an over-torque switch that could have failed as well.
if thes are things you feel comfortable checking, you may be able to save yourself some money by repairing it yourself.
if not, the cost of having an electrician check it for you could easily exceed the price of a new unit.