What's the difference between a regular Facebook account and a Fan page account?
 

how do they differ?

Uhmm... No one visits fan book pages?

Just kidding but not much difference really.

A real page will need you to approve everyone. A fan page can just be "liked" and people can interact with it.

At least that was the major difference last time I set something up, but they change stuff all time.

That and pages have the ability to see some stats

A fan page is normally used by companies or someone selling something as you don't have to approve every like, it's done automatically for you. It's also easier to design to look similar to your website, the most popular way is by using iFrame.