You can render out as .avi but it's an uncompressed .avi so will be huge. You're best bet is to render out as frames, I prefer .tga, and then use them in Premiere or something along that line to create your movie and it will give you the freedom to use any format and codecs installed on your system
Red bellows of flame have blackened my stones
Convulsing my frame and cracking my bones
Hell's dragons of steel who roar in their chains
Crawl into my caves to suck out my veins.....
-The Mountain P.F.M.