Do you have any integrated graphics related to Nvidia? I don't know what system you are running, XP,Vista,7 or your motherboard and would be a great help if you could post some specs.
Aside from that, go into device manager, see if Nvidia is listed in the list. If the card drivers are listed, you can uninstall the driver and possibly remove the software from there. Look in your add\remove programs list as well, see if there is an entry for Nvidia, uninstall from there. Simply deleting a folder may cause issues and would wait until you are sure this was for your card only, that everything is uninstalled correctly and no other programs are using this folder that may be associated with Nvidia. If everything checks out and the folder remains, then you could likely delete it.
My old Nvidia Graphics Card packed up and I replaced it with a Radeon Card. The computer is now working fine. However I wondered if it would be safe for me to delete the NVIDIA folder, when I click on it a folder shows saying "Display Driver".
Would I be correct in thinking anything NVIDIA is safe to delete?
Would much appreciate any advice.