Simple motor controll, 2 motors/wheels. on/off

I have, what seems, a simple task i need to do and i decided arduino would be the best way. The final result needs to do an obstical course at the push of a button. i plan on using just two dc motors to power two wheels and such use a simple on off motion to direct the robot and through trial and error change the delay times within the programming, i have a basic idea of the programing side of things but as for the electronics i am not so experienced.
can anyone help with this project? any simpler/better ideas would be appriciated.

I've seen similar questions like this, and have found many through search feature but here is a schematic i've made to control a dc brushless motor; The biasing can be found by googling "2N4401 datasheet" and is rated MAX 600mA.

Also, you can check this topic for additional information.
http://arduino.cc/forum/index.php/topic,97970.0.html