In order to view your menus on your iPad, you must make sure your have Adobe Reader installed.  You can get the Adobe Reader for free in the App Store. You will only be able to view your menus in Adobe.
Once installed, all you need to do is open the email containing the menu file attachment, click on the attachment box (after you click on it, the box should change to say pdf.) Finally, click and hold the box that says pdf; a small window will open up that gives you a few options- choose the option that says "open in" and then all you will need to choose Adobe Reader. It will automatically save to your Adobe Reader documents on your iPad.
To read your menu (after it’s been saved in Adobe) just go into your Adobe and click on Documents at the top of the screen. When you are home and are ready to email it back to yourself to save on your home computer, all you have to do is open the document on your iPad and click on the little box in the upper right-hand corner of your screen. Your option to email the document will be right there.