Can anyone help me??? im in the process of making a trap and i want the door to automatically open.. not sure on what type of motor to use for it.. please help!!! 
What do you mean by “automatically open”? When you throw the trap down? When you stomp the pedal? When the trap hits a wall?
Easiest motor to use would be a servo and the easiest way to control that is one of the various microcontrollers out there IE: arduino, basic stamp, PIC, ETC. These will all require knowledge of or a willingness to learn electronics, soldering, PWM and programming.
A cheaper alternative is to find an existing product, like a toy or tool, that does the required motion and hacking it into the trap.
There is this:
WOW thank AJ that will work perfect!!!