The file size when batch rendering to .avi and not compressing is huge. If you don't want to use any of the programs mention by stwert and want a fast result you should use some form of compresion. But i wouldn't recommand it because the quality isn't that good. I make use of aftereffect to get some good quality and not a huge file. There use to be a free tutorial on SM about Render_Movie_Globals.