I'm running a PC, and I wanted to check the TYPE of memory on my computer.  So I shut down WINDOWS Xp: Home Edition, opened up the case and took out a stick of memory.  After inspecting it, I plugged it back in and my computer stopped working.  Whenever I try to turn on the computer my monitor no longer gets a signal, the power does not shut down after holding down the power button like it's supposed to, and the Dvd-rom and CD-RW drive both do not respond to their 'open' buttons. I also tried to put in a different video card to see if the card was the problem but I saw no difference.  Any help or response would be appreciated. I do hope you demagnetized your hands before removing the  memory stick?

If you did, did you properly push the stick till it is secure?

You SAY you took out 'a stick'.  I'm assuming you have more than one so take that stick out again and try booting without it.  If you're GOLDEN then that's cool, if not you may have DONE something bad.You should turn the switch on the power supply off or unplug the machine, and take static precautions, before handling your RAM sticks.

Make sure it's not in skewed or backwards.