[Ethereum] How to install Solidity on Windows

It does not seem that you compiled the source? You just declared a variable holding the source code. That's the main problem.

Also, apparently, your function greet() is not declared with the keyword constant. You'll therefore have to call it with greeter.greet.call()

PS : no need to do this complicated stuff to create your development chain. Just run get --dev --mine --minerthreads 1

What is actually happening in sub-dividable token contracts (and ETH itself) is that the actual unit is tiny. Really, really tiny. A single ether is actually just 10^18 wei. For the sake of the users, it's shown on the various frontends as a decimal number of ETH.

The same principle applies in token contracts. Internally it's just a standard uint holding gargantuan numbers, but when displayed it's converted by the frontend into a small, human-readable number.

This is so that the token can be divided in nearly any amount, and if it suddenly needs to be divided even more then all it takes is adjusting the frontend to handle it.