Sure you can use it as a server base. But its only really effectiv for websockets and more webbased applications.You're not insulting me, that's just horrible analogy.
Most web applications don't run on "OS level", they either run on top of a VM (although optimized) or interpreted. Also node.js is fast, as it was built with concurrency in mind. When it comes to SQL databases, it's not as straightforward as PHP, but it is faster. And you cant really compare when it comes to databases with JSON as the query method. Also node.js uses less resources compared to PHP.
Wouldn't recommend it for a project like that.