What games to but this chrismas

[Everstar]

I own a wii and a 360 and i was wondering if i had to choose bettwen 4 games on both systems combined what should i get?

I enjoied oblivion, gears of war, mass effect, and i dont have it yet but i love Super Smash Bros Brawl.

I love games that will give me a challange and games that are long.