I would have to say wood...and while I love the sound of an aluminum bat crushing skull (oh, from the movies) and it is easier to clean (no stray bone fragments), the wodden bat (broken or not) can be durned to dispose of the evidence.

I'm old fashioned. I go for the wood ;)

I would go wooden bat because wood is really hard and can hurt the person really bad. Plus I would hit the person on the head and knock them out and call the police.

Great question! The Aluminum is new and all the rage but since i'm an old fashioned guy and like to here a big clunk when i'm bashing in the heads of those dumb babys

Wood is awesome when thick. I mean there are cases called 'blunt trauma' specifically for these weapons :)