bluescreen upon plugging in anything (ntoskrnl.exe mystery)

ever since downloading a "critical" update from microsoft
in november, my computer gives me the blue screen of death
whenever anything other than my keyboard, mouse and
monitor are hooked up to the machine. it says,

"page fault at nonpaged area", amongst other gibberish,
and mentions a kernel file (ntoskrnl.exe), and won't
restart.

i just bought an iPod and installed a usb 2.0 card, which
causes the computer to frig up on me whenever i plug it
in. please help me, for the love of god!! email a response
to ebolamonkey@hotmail*com