Just built my first rig...HELP

Recently after many years I found myself with the funds to build my dream machine. So here it is, a FIC AD11 MB an AMD 1.2 gig proc retail(boxed) a western digital 60 gig drive @7200 rpm 512megs of DDR (2100) a leadteh gforce 2 ultra, a DVD and A 12X cd burner.
The initial building and installing the os was a dream, I was shocked as I was told what I was about to do could set me up with permanent brain damage.
Everything went fine except as soon as I plug anything into the serial ports, when I go to shut down the machine reboots. If I pull the digital camera and palm pilot out of the serial she shuts down just fine. I am running windows 98 second addition and was told there was a fix for this problem, I down loaded the fix and still the same problem. What gives, is there a conflict? I am totally befuddled and everything I read leads me no where. My knowledge of computers is fairly limited as I am new to all of this. Please help thanks in advance, Robert