Most I have ever spent from a store is 80 for NBA JAM on release day. It sold out everywhere and I found it at babbage's way jacked up in price and just bought it anyways. Totally worth the purchase.
MMO played WoW for 3 years I think so around 650 and then Dota I am at 240 bought in the ingame store but if you include things outside of that im not sure but lets just say more. LoL would be in the range of 2-300 as well.
so i looked at it on low settings on pc my guess is thats what it will be on 360 runs fine but some of those textures are like n64 quality it seemed, but should play just as well, still really enjoying it but it takes me a few matches to get to the point where i dont just die. I play too much like halo when i start every time, yea that just doesnt work
I would add these (yes some have come out on other platforms later but still thought of as xbox games to me)
Super Meat Boy
Pac Man CE
1 vs 100
Banjo-Kazooie: Nuts and Bolts
Dance Central 3 (with all the 1 and 2 songs imported over)
Forza Motorsport 4
bet i covered the rest that people would want with this list other than the big ones already stated