Starting up a YouTube Channel?

Hi, I recently bought a HD PVR and I am going to start doing YouTube videos, but I don't know of which game? :D My games: CoD Black Ops 2 GTA 5 Saints Row 4 Just Cause 2 Also, I don't know how to live commentate. My YouTube: www.youtube.com/mrcodbiscuit My XBL Gamertag: DroneSource