What Should Be A Simple Project

I know nothing about programming - I'm a Hardware Guy more than anything, I've tried and just can't grasp this stuff. What I am in need of is a program for when I set up new computers. It needs to work with Vista and Win7 and it needs to do the following:
--Create A Primary User Account - Admin with a Password and ask for the Username and Password I want to enter.
--Create A Secondary User Account - Standard User, no password and ask for the username.

--Needs to have a button that will allow me to delete the Secondary User, delete the Primary User password, Enter a new Primary User Name, and Change the PC Name (Full Computer Name).

I work for a company that sells PCs and we usually set up a Primary Admin account with password and then a secondary account so we can allow customers to get into the PC and look around without messing anything up... then if we sell that display PC we have to remove the secondary account, change the admin account to the customer's name, remove the admin password, and change the Full Computer Name to the customers name - I'm wanting to automate the process. I don't care how basic it is as long as it will do all of the above things mentioned in a shorter time that it currently takes me.

--I was successful at creating a batch file to do part of the work but it doesn't give me control I would like - such as entering a new username and deleting the password.

I'm looking for someone who can do this at no cost -as I do not have authorization from my company to pay for this- this is considered more of a luxury to me than a need for them. If created I would like autorization from the creator to give this out to my other locations as well - if not it's ok and I understand!