To answer these questions properly one can fill pages.
So you'd have to be more specific.
Here are some short answers.
Is Qutbism a diffrent name for the Ikwan?
Yes you can say that. This movement was started by Sheikh Hassan El Banna. And it had a noble purpose which is fighting the British occupation in Egypt. Then it became a mafia, which mad Sheikh Albanna to condemn them. Then came Sayyed Qutob and put the basis of the movement that terrorized muslims in the 70s, 80s, 90s. in Egypt, Algeria and other places
Do the Whabbis and Ikwans have have diffrent beliefs?
In short yes. But both act like a polymorphic virus. they may be very different from small faction to small faction.
Al Zawahiri and bin Laden are example of how they may merge in some incidents.