Hmm... Rumpel's dagger so I could control him and make him be with me forever!! *evil laughter* xD Ohhh and Graham's 心 would actually work for the same purpose too with him lol. No, no wait...I also want the magical hat which gets 你 to different worlds!! Yep, that's my first choice:) haha
I would steal... Henry's storybook to read all the stories again and again, a magic spell book to learn magic though I would use it for good not like Regina, Ariel's bracelet so I could become a mermaid, and Emma's yellow bug because it is awesome and super cute.