I will suggests you the perfect solution to secure your Gmail account. According to my personal experience, I also searched for a same issues to secure my Gmail account, after lots of searching i got a perfect solution that helps me to backing up all my Gmail data with attachments to my PC. The tool name is sysinfo Gmail backup tool, Which is very user friendly.
This tool also provide us option to delete all the Gmail data after backing up. This is my personal experience that i share with you all.