1. She purchased the system with ubuntu without knowing what ubuntu was.

2. She was told she could get windows for it but then changed her mind based on the opinion of a tech support person even though it went against her experience of using the system up to that point

If she had researched what ubuntu was she would have known it was free and could have downloaded it at a later date, the tech support person could also have told her, then this whole incident would have been avoided. Support personnel are most likely encouraged to stop people switching back to windows because of the costs of getting windows to the end user.

Dell needs to add a guide on what ubuntu is and isn't and make it available on their website and on the first boot of the system.