writing a paper on skiing is a terrible idea. there's just not a lot of good reliable source data on which to base your research. i mean, i get it that everyone here is passionate about sliding on snow, but that doesn't make it a good topic for school.
definitely do it on fighting in hockey. it has evolved SOOOO much over the past 40 years and there is quite a bit of data to use in your research. Plus, as previously stated, it'll make for a kick ass presentation...punny punny, i know.