I'd have to vote for 2002. The Native-themed movies of that year include The Business of Fancydancing (perhaps my all-time favorite Native movie), The Fast Runner (Atanarjuat), Skins, Spirit: Stallion of the Cimarron, Skinwalkers, Windtalkers, Brotherhood of the Wolf, and Wendigo. The Business of Fancydancing is perhaps my all-time favorite Native movie and the next four are all above average.
Check 'em out at The Best Indian Movies. I've reformatted this page to make sure it displays correctly. I've also added a section on aboriginal and indigenous films such as Rabbit-Proof Fence (another favorite) and Ten Canoes.