The arc trainer kicks my butt, which is similar to an elliptical machine. Stair climbers will kick your butt too. Sounds to me like you are very active already. No matter what you do, it will take time to lose weight
. The faster you lose, the more likely you are to gain it all back. Find a calorie/exercise level you can live with for the rest of your life
, not just until the weight comes off.