I would run 4 separate wires in conduit. Red, black, white and green. If you reuse the range wire the circuit will be limited to that amp draw even if you use bigger wire. So if the range circuit is not big enough you will need to replace wire all the way to breaker plus breaker. The wire going out to garage can be increased in size to make up for voltage drop, which depends on distance, amp draw and type of wire used. I would run #6 all the way from panel and use 60 amp breaker.
As far as conduit 1 1/2" for power. I would run a separate 1" or 1 1/2" for any spare wires you might want in future, phone, cable, data, you never know what you might want in future.
