Which motors to choose?
A 12 volt DC motor is good for dragging items, but then again it depends on the items weight. Stepper is used for millimeter precision, like 3D printing. Servo is an DC motor with precision for 180 degree movement, like robot arms. If the moving object is over 1kg you should look into geared DC motors or even the stronger brushed motors, or geared brushed motors. Whats the max weight?