Place your cursor over the person’s picture to see the green call button and click it to start the call. To call a different number, click the down arrow on the green call button.
The green call button displays different ways to call someone. If a person is online, you'll see Video Call or Call. When your friend is offline in Skype, and they have a phone number stored in their profile, the call button says Call, or if multiple numbers are stored, the call button says Call Phone, Call Mobile or Call Home.
Learn how to call an Address Book contact in Skype.