1.25 HP Garbage Disposal Blows Fuse
Something is wrong with the disposal or something is wrong with the circuit breaker.  It's normal operation to turn a breaker all the way off before resetting it.  I believe that's how all of them work.

To diagnose the problem, you're going to have to measure the power usage of your disposal.  You can do this with a "clamp meter" that measures amps or a more consumer friendly meter like a "Kill-a-watt" brand power usage meter.

If the disposal never goes over 20 amps but the breaker is still tripping, the breaker is most likely bad.  If it goes over 20 amps then something is wrong with the disposal and replacement is probably the best fix.