QQ is similar to Skype in the U.S., where you can chat live online, and also use video and audio to see and hear each other, if both have computers with a camera and audio (QQ is also used with cell phones in China, and they usually don't have video or audio capabilities, from my experience).
QQ also has an email feature, which allows people to email each other using their QQ address...so YES, you can email her using any type of email address, yahoo, hotmail, gmail, etc.
She may or may not have intended it, but you can also use the QQ aspect, and chat with her live. The numbers in her email address, before the @ sign, is her QQ connection.
You can install QQ in your computer, and I think the latest version that is setup for English speaking people, is called the "international" program...Google "install QQ program" and I'm sure you'll see lots of places to download it, or maybe someone on the forum knows the best address and can provide it to you.
You will not need a QQ account just to email her, but you will need a QQ account in order to chat live...