requesting a row

Im making a login script for php/mysql. At the moment I have a form that sends the information of the field to the database. (creates user).

Now I want to make a form the posts the information to another page.
That page will check all rows for a match for both of them. (logging in).

So it's not really requesting a row, but checking them for a match.
Can someone write me a script please!!! I've checked for logon scripts everywhere that are as simple as I'm describing.
Can someone help me!!!

I'm acctually creating a game that you can login with.So when I log in, is it possible that in the table where the user is, there is one column that has the amount of money that a user has. And when you log in it has a variable named money that is the same amount as that column. The the variable changes depending on what you do and When the user decides to log out or close the browser, the money column is updated with the variable.

Can you do such a thing? because if so then, That could be the answer to a very, very big problem.