You can keep the card, but first we want to make sure your system will be OK before continuing to the next step. So, make sure you can power on the system and it starts normally with all networking and related software/hardware uninstalled.
Delete the MSN/Microsoft Network icon off of your desktop. You'll be prompted some blather about it can't go to the recycle bin. Click OK. If you don't have any add/remove optional components related to MSN/Microsoft Network/Networking, then great --> Continue.
If any software related to the NIC was installed from Add/Remove Control Panel or from your start menu with an uninstall process, use this to remove the drivers/software for the Realtek card. Don't reboot. Shutdown instead and remove the Realtek card.
Before continuing, make sure you don't have any other networking component installed which you are using for some other function (like a VPN adapter, NetBEUI, etc.) <-- MSN/Microsoft network MIGHT have components listed here if it was ever installed.
If you still have Network Neighborhood on your desktop, networking hasn't been completely removed. Rick click it, click properties, and remove any component you see remaining. Reboot.