How to use DataStore?

I'm looking to have IntValue's That save and load when a player joins and leaves. Using the onClose and the playeradded.

What I am looking to do is have scripts that access these for various things such as changing the players walkspeed and maxhealth.

I have read http://wiki.roblox.com/index.php?title=Data_store and it didn't really provide me with what I needed to know.

What the script is just needed for is to load when a player joins the game and saves when they leave using the 'game.OnClose = function()'