plug & play devices

I have a dell dimension 8400 with windows xp home edition. The motherboard was replaced and now ever since that all the system would not automatically find the drivers for plug & play devices. I have also firewire card because I recently bought a canon elura65 camcorder, and it will not find the camcorder either. I tried to reinstall the os from the cd windows home edition and now that did not work. Now when I turn on my computer because the install did not complete it ask me what I want to do of these two options 1. run windows xp home edition or 2. run windows setup. How do it get rid of this and how do I fix my system so it will find the necessary drivers for the USB and firewire devices??