I was hooking up another monitor onto my computer and went to the nVidiea control panal (I am a nube at this). My screen turned black and I tried restarting. The windows staring up works but... when it gets to the loggon screen it all turns black. All my important files are on there. I tried going into safemode but the nvidea control panal isnt there.

When windows goes to the logon screen it has changed from 16bit colour to the graphics that you have set for your GPU. Obviously something is amiss in what you have set, and you are now blind. Restart in Safe Mode [it uses 16bit colour], access your graphics as before and be sensible this time. No files are lost. Good luck.

while booting press F8 to get the safe mode wait while it shows the desktop press right click on your mouse and press properties and set
by the way the nvidia is in the Control Panel

Put the cable back into the onboard graphics port.

Open bios
Set Primary display to AGP if the card is AGP. Unslect Onboard if the option is there.
Save and exit
Quickly put cable into grahics card vga