You don't absolutely NEED to disable the onboard graphics, I think doing so just uses less power and creates less heat. You disable it in your BIOS menu (press DEL in the earlier stages of booting your computer)
go to control panel click add/remove programs then uninstall nVidia Display Drivers
turn computer off.
Open computer case
Since your current card is integrated, theirs nothing you can take out. You'll see a bunch of different slots, just put it in the once that it fits in. If your case doesn't have fancy built in clips, you'll need to put in a screw to hold it in place. Plug in the correct power cables if your card has power connections
Close case
turn computer on
Don't bother with the drivers on the CD, their likely out of date. Go on to the website and download the most recent drivers
install drivers
when finished reboot computer
right click/properties/change resolution to desired resolution
you have succeeded at winning the mission!
Fixed a few things and added more detail on the installation.
but what if the card is defective and didn't know that when i unistalled my old graphics card?
Well first check to make sure you did everything right and you plugged everything in (Actually do this before you even turn the computer on) if it still doesn't work, then take it out and switch back to onboard. If you bought it at a store, just get an exchange. If you bought it online, you'll have to go through the return procedure of the company you bought it from, which means about a week of waiting and usually paying for your end of the shipping. I've bought a lot of things online and never had DoA issues, so you probably don't need to worry about it.