Thanks for filling me in on this info. You can generate a set of pages to work with PayPal standard using the checkout wizard, you would just need to ensure that you enter your credentials in here.
The tricky part about using Payments Standard is how you handle the response from PayPal. You will not get a response at the time that the user submits the transaction, instead you will get a response sent via the IPN post that occurs. You will need to enable the IPN and specify the page for it to post to in your profile.
To get Payments Standard implemented so that you can send the email when a transaction is successful you will need to have an IPN page in place. On this page you will need to do all of the proper checking for the transaction then you can update the order in your db and set it to successful and send out an email receipt.
PayPal has some great tools for creating the IPN pages in the developer center. You can have it post test responses to your IPN page to make sure that it is working correctly.