How To Defeat General Raam Gears of War

Hint - Berserker Beat Down
To defeat the Beserker at the end of act one, simply dive to the side when she charges at you. Run through the doorway to your right and continue to the door at the end of the room and face your back to it. Get the Berserkers attention by shooting at her or revving the chainsaw then, dive away at the last moment when she charges causing her to break the door down for you.
Continue this to get through the next two doors. When you finally lure her into the courtyard simply use the Hammer of Dawn twice to take her down. [If Dom is killed the mission is over, so revive him if he's knocked down]
Hint - How To Defeat General Raam:
In order to defeat Raam, you need to have grenades and a sniper rifle which is supplied in the center of the room before entering the boss arena.
After entering the arena, stay behind the wall you ended the cut scene with. This is important because you need to maintain your distance from Raam. Also, it helps to command Don to "cease fire." This will make him run back towards you keeping him alive longer to distract Raam.
The trick is to get Raam's swarm away from his body. In order to do this, you need to throw a grenade at Raam. If successful, the swarm will disperse giving you clear head shots using the sniper rifle. Repeat until he’s defeated.
If you don't defeat Raam by the time he reaches your wall cover, move in the opposite direction he does and shoot when the swarm disperses. You will take damage from Raam’s machine gun, but you stay in the light which prevents the swarm from killing you.