Geforce 9500GT driver help

I have a nvidia geforce 9500Gt and Im using ubuntu linux 12.04 and I have the card displaying the screen but i install warthunder and it told me i need to install a new graphics driver. I have downloaded the driver that i found on the nvidia website but it wont install i open it and it gives me a blank white notepad screen. Please help aslo give detailed instruction I ma new to linux thnx :)