I would say a complete up grade in other words a new system. Your CPU just makes min requirements. Your OS of 32bit I don't know for sure it might be. Your GPU is below min requirements.
You are 1 gig over min ram. I would not take a chance on this system even if you upgrade your GPU everything is at min or below. here is the min and recommended requirements for BF3. I wish you and your friend good luck.
]Minimum requirements for Battlefield 3
•OS: Windows Vista or Windows 7 •Processor: Core 2 Duo 2.4 GHz or Althon X2 2.7 GHz •RAM: 2GB •Graphic card: DirectX 10 or 11 compatible Nvidia or AMD ATI card, ATI Radeon 3870 or higher, Nvidia GeForce 8800 GT or higher. •Graphics card memory: 512 MB •Sound card: DirectX compatibl sound card •Hard drive: 15 GB for disc version or 10 GB for digital version
Recommended system requirements for Battlefield 3
•OS: Windows 7 64-bit •Processor: Quad-core Intel or AMD CPU •RAM: 4GB •Graphics card: DirectX 11 Nvidia or AMD ATI card, Nvidia GeForce GTX 560 or ATI Radeon 6950. •Graphics card memory: 1 GB •Sound card: DirectX compatibl sound card •Hard drive: 15 GB for disc version or 10 GB for digital version