The boot animation seems superfluous to me. While exploring the file system with
Root Explorer I stumbled upon a file called bootanimation.zip in /system/media so I renamed it to bootanimation.zip_ and rebooted. The animation was replaced with a simple "andoird" logo.
I think there are also other programs out there to allow you to put a custom boot animation there (it is just a zip file of a sequence of pngs), but I prefer the simple approach.