If it doesn't start up at all, you may need libopenal installed.

If It still doesn't start up at all, you may need libvorbis installed. 

If it STILL doesn't start up at all, you may not have hardware OpenGL accelleration. *This is absolutely required*.  Install appropriate video drivers for your video hardware.  You can still attempt to play the game in software mode by adding +r_allowSoftwareGL 1, but that's stupid and for 1fps-loving insane peoples. Don't try this at all.
