Will crank sensor cause car not to start and power windows work?

A faulty crank sensor can absolutely prevent a car from starting because the engine computer needs the signal from the crank sensor to know the engine's rotational position to properly time the fuel injection and ignition.

However, the power windows typically run off the battery and a separate fuse/circuit, independent of the engine's operation. Therefore, a bad crank sensor wouldn't directly affect them. If your power windows work but the car won't start, a faulty crank sensor is a strong possibility.