Website Compatibility and a couple of other bits

I have a website which is acting the way that it should in Chrome but I have just been advised that iPad users get an 'undefined' error when they try to join up and use the Paypal button. I really need the site cross checked and fixed up for all common browsers. I need this task done immediately as our site is live and iPad users have let us know they can't join up. Also, there is a piece of information that doesn't flow through to the email that I receive when the button is submitted. The membership type (price) information doesn't come in with the email we receive when a user presses the button. I would like this to appear on the email I receive. Finally, none of the fields actually force you to enter information into the fields and you can submit without entering the info. All the fields should be compulsory except for Puzzle Preference 2 and puzzle piece count. Website is [login to view URL] and problem page is [login to view URL] Please have a look at the site before you bid and let me know that you are available to fix this immediately.