Glona,
One question is going to lead to another, and all of the answers are in the Experiment and Modifications of this forum. As I understand it you want to harvest a diode from a DVD reader. You probably will not be happy with it but if you do, you need to regulate the current going to it. I have no idea how much current a DVD reader diode uses. I am only familiar with DVD burner diodes.
I think you have all the parts you need except the LM317 regulator...these are available at Radio Shack. For the diode's current I am guessing 20ma's or so. So you would also need a 62.5 ohm resistor. Radioshack has 68 ohm resistors but you might have some with your lab. This would be close enough.
The value of the capacitor is not critical as long as it is 10uf 16 volts or more.
With the above three components and a power supply that is at least 6 volts, you can build a driver.