The ice mission near the start is easier than it looks. Collect as many crates as possible without using any utilities, then use the jet pack to get up to the next section near the guard. Collect all the crates there and stand on the polar bear's head. Point the flame thrower at a spot just to the left of the guard, and fire. You should get through the barrier protecting him, and the flames should send him into the water. Strap on your jetpack and get to the flamethrower. The flamethrower is the most important item on this level. Use it to shoot at your opponents. If it does not immediately kill them, shoot a fire barrel to finish them off.