Nickelodeon Dance 1 & 2: Brutally easy, no skill required.
Adrenalin Misfits: Requires a second person, but the game is not hard if you know what you are doing.
Cabela's Adventure Camp: Not difficult and very fast.
Kinect Fun Labs (all free but only 50g)
Sesame Street TV: Expensive DLC, but stackable and easy if you can get Smartglass to work.
Kung Fu Panda 2: Fast and easy fighting game
Puss in Boots: One or two challenging gold medal times, but that's it.
Penguins of Madagascar: Easy and fast.
Easy with caveat:
Victoriuos: Some have had major issues with a mini game or two. I had no issues.
Game Party: Easy if you have 2 people
Michael Phelps: Can be very hard in the final few races
Let's Cheer: 5 stars on every song is pretty hard, but quick.
I know you have Worms 2 on your boost list in the Sub forum. Feel like tackling the multiplayer this week? Apparently they patched the game so that a quit counts as a win for the player that sticks around, so it should be pretty straight forward to boost.