Do I keep turning Safety off and killing my wives and other villiagers?  Will the future be different if i kill all the people in one town?  I keep killing everyone and would like to know if that will be a huge problem later or not.

At first I didn't notice this was in the Fable II forum. That was a little disturbing....
 
Anyways, yea, I believe shooting everyone could be a problem, depending on what stage of the game you are in.

Nope does nothing except make you evil and look all crazy. 

You can mess up the economy, though.  
 
Some people would want that.

" Nope does nothing except make you evil and look all crazy.  "

" You can mess up the economy, though.   Some people would want that. "

How are you "accidentally" killing all these people? Do you just walk around shooting your crossbow or rifle?  
 
I have to say though and Villager who kicked my dog did not see another day. 

Well if you do kill all the people in one town it's gonna pretty much destroy the economy of that town for one thing. My brother once went on a huge killing spree in Bowerstone for fun only to find that he'd absolutely ruined profits from all his stalls, shops and houses he was renting which were pretty much all in Bowerstone.

Just to clarify, I'm not accidentally killing everyone.  And to clarify further I have not gotten very far in the game.  In the first adult part (where you find your house in the gypsy camp), I found the "safety off" button and slaughtered everyone who didn't have the foresight to start running when I started chopping.  Then I opened up Bowerstone Market and before I did the first quest that takes me on the path to the town where the bridge is out and all that, I found way more people to kill and tougher opponents (and more experience) in fighting the guards.  Plus its funny when you get a list of crimes that says like murder x24, resist arrest x6, attempted murder x3 and vandalism x1, and all they do is have you run off and do the same community service as if you got caught stealing.  That's funny and ironic.  Plus the experience I get from killing guards has allowed me to level 2 alot of spells and now kiling them off ad infinitum has become a pretty simple process.  I'm just wondering if anyone else has come across this, where the "ability to kill everyone but little kids" mechanic has become more compelling than the story itself.  Even when I did move on in the story, I quickly got bored trying to make money and do the story that I just decided to be the terror of this next peaceful villiage I came across.  And this time I ended up murdering my fiance because she wouldn't marry me anymore....

i dunno, when i played through it didn't really do anything. which was sort of disappointing but w.e

The economy will suffer, that means cheaper everything. You will be hated, that means more expensive everything, you will be feared, that means cheaper everything. You will probably need to find a breve wife/husband if you want to marry, beside of that, all changes will be isolated, but I think the main difference is the lack of change when compared when playing good/virtuous. Don't believe me too much, though, I still have to play (really) evil to check.