Sounds like you're set with the mall because it's definitely safe, clean, has plenty of natural life and is generally busy. The food is pretty average for a mall, far from being the ideal, but far form being hte worst. There are only three theaters I know of in Providence, and two of them, the Avon and Cable Car, are more specialty theaters. It doesn't really matter though since Providence Place has 20 screens + the IMAX.
Parks and nature stuff is not really obviously accessible, though I know there are various ways ot get involved with that kind of thing through campus groups. I'm not an expert there as I haven't really sought it out since at Brown so I'll tag in someone else for that one...
Btw, I'm a NY guy mallrat, hence my discussion above...I assume you're a girl? I don't know too many guys who ask about the local mall

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