Hello Vitor, and welcome to the friendly Camera Labs forum!
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The D5100 certainly is a very competent camera, and with a stabilized 18-200mm super-zoom a kit that should be capable of capturing most situations.
Just don't expect it to get you good macro-shots and keep in mind that image stabilization can only help avoid shake but not blur from fast(er) moving subjects.
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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