Canon 50D automatic expososure

[Yamaha32088]

I have the Canon EOS 50D and have a couple questions. When I have the camera set to full Manual mode if I am in a dark room the picture is extremely dark in the LCD until I hit record which then it will lighten up to expose the picture. I would like to be able to have this set to where I have full control over the exposure so it does not do this. Also I keep reading about RAW video mode I have my camera set to show RAW on the top of the camera lcd, does this mean the video is RAW? I have is set to record CBR at 1.4x but there is an option for VBR(Qscale) and FW default no RAW. Sorry for the newb questions but I have not been able to find my answer through googling.