If you don't want to use a mcu, you'll never be able to let your robot do anything else than being a photovore.
But if that's what you want, you'll need a voltage comparator (741) and some photo diodes.
But I strongly recommend using a mcu. It'll be much easier...
And for the motors, naturally ungeared motors spin very fast and have very low torque.
to drive a robot you'll need geared motors. And you'll need motor drivers.
It would be easier to use modified servo's to drive your wheels, but then you'll need a mcu.