Lucy is having trouble with Chrome and she's tried to remove it, but can't. Leo says it's probably gone into "metro mode." If she sees the hamburger menu of four lines, click on that and she should get out of it. It may also be the sign of an infection that has modified the browser. She should try pressing F11. That will take it out of full screen mode. At that point, she should be able to close it. CTRL-ALT-Delete will work as well.
Lucy should reboot, and tap the F8 key to get into safe mode. Then she should be able to uninstall Chrome from 'Programs and Features.' If she can't close it, that's almost always a sign of malware, like a browser hijacker. And a poorly written one at that. Lucy should check out futurecrimes.com to learn tips for avoiding malware, even though she has malware. Antivirus won't protect her from herself if she isn't being careful.