Can you transfer EPUB and PDF books from Windows 7 to iPad 2?
Yes. But in order to transfer your data to your iPad, you will need a utility that can help you with this. You can visit the Software Informer's website in order to find a program that can suit your needs. I suggest you take a look at ImTOO iPad Mate. This utility is fully compatible with your operating system and can work with your iPad device.
This is very easy with syncios free ios manager, here is tutorial: http://www.syncios.com/transfer-ebooks-to-ipad.html