dude, you really need to be way more specific. not just skiing, big mountain or freestyle- you simply can't say shane mcconkey is better than t-hall, they just aren't comparable.
as this is a freestyle site essentially, i'll assume you mean freestyle.
probs best of last 5 years would be:
tj schiller
tanner hall
cr johnson
candide thovex
jp auclair
i'm sure ppl will disagree, but candide and tanner are undisputable.
as for results, google x-games results for superpipe and slopestyle since 2000.
hope this helps