Optimizing performance on Windows 7 with an older Office version can often involve regular maintenance tasks. Defragging your hard drive, clearing out temporary files, and ensuring minimal programs run at startup can make a difference. For security, using a reputable antivirus that still supports Windows 7 is crucial. Programs like Malwarebytes or Avast offer options compatible with older systems. It’s also wise to ensure your firewall is active and consider additional layers like an anti-malware tool. Have you thought about trying a lightweight Linux distro as a dual-boot to maintain access to critical apps with better security?