Morrowind notwithstanding you forgot the Might and Magic series, which presented awesome skeletons from the first one to the last, including the Heroes of Might and Magic spin-off, and YOU could be a skeleton... well... the mage in your team could become a lich with awesome look... And in Heroes you had a team with Skeletons as the bulk of their forces AND skeletal dragons as a bonus, as well as skeleton Heroes with one that stands out for his personality and grim reapper look. Want a tip? Look at my name.
Time Splitters is, in my opinion, the best, no second best, multiplayer game the Cube has to offer. Second after SSB:Melee. It has more than skeletons. It's got all sorts of random-ass characters than you can fire a minigun at.
Mr. Bones, the blues musician from Saturn/PS1? Oh well, it's a little obscure. But big cheers for mentioning Undead Knight from Guardian Heroes/best fighting game ever.
I'm surprised that Goof Troop, a game that starred both Goofy and his son Max, was not mentioned on here. There was a dual of bosses in, I think, the eighth level. The way they fought you was by them throwing a boomerang made of their own bones at you. Additionally, the Goof Troop had a fantastic soundtrack and is probably why I still even remember that damn game.