PCB Footprints - Using OrCad PSpice and PCB Editor

[staticshock]

I've used PSpice quite a bit to be familiar, but have never used the PCB Editor or any kind of PCB software. Anyways, I'm in need of some help on understanding the footprints needed to create a PCB design on the PCB Editor. I've watch a video on YouTube on how to use the PCB Editor, but I'm not entirely sure of the exact footprints to use as the person in the video doesn't go into detail about that; just the process of creating a design. This may turn into a thread with multiple questions. Starting off, I'm going to edit the resistors in my schematic to specify the resistor footprints. I've come across the .dra files in the Cadence files. Can someone explain what the differences are among res400, res500.dra, res600.dra, res800.dra, and res1000.dra??? Do they have different size specs, does it matter which one is selected, etc.

[CadenceAE]

I recommend using the PCB symbols built for the part as specified by the part vendor.  You can find these already built for free at websites like snap-eda, OrCAD ultra librarian, pcb libraries etc..   

Those symbols correspond to common resistor sizes 0402, 0603 etc...