I'm new to this game, and have managed to get a lot of great people, what's there purpose/point
Rach

Great People can help your score. When they're in a city, you can use Great People to build special buildings, help discover a technology, and boost science/culture/production depending on who it is. You can also trigger a golden age when you have two of them (but it has to be either 2 great scientists, 2 great engineers, 2 great artists, etc.)

Thanks.

I've got 2 of them (can't remember which) I've probably got 5 great people just standing around doing nothing.

Is there a point to getting the Golden Age?

Golden Age's are usually triggered automatically and only apply for 20 turns. During those 20 turns, your cities will produce things quicker, you'll be able to get more scientific discoveries quicker and other benefits.