HOSTS File

I searched my computer for HOSTS and it gave me a lot more than one.

HOSTS C:\WINDOWS\I386
LMHOSTS.SAM C:\WINDOWS\I386
Hosts C:\Program Files\Spybot -Search & Destroy\Includes
hostsfile.hst C:\Program Files\Webroot\Spy Sweeper\Masters
hosts C:\WINDOWS\system32\drivers\etc
HOSTS.bak C:\WINDOWS\system32\drivers\etc
Imhosts C:\WINDOWS\system32\drivers\etc

Which ones are not necessary and which one was the real one to edit in the first place?

hosts C:\WINDOWS\system32\drivers\etc

Sorry I should have said that the Host file is located in the directory above. That's the one you wanna edit to block sites/ads and others...I use a very useful tool that came with k-lite it's called "Host file Manager" very Useful. I havent touched the other ones.

Jusr for reference:

HOSTS C:\WINDOWS\I386 - This is the original one that windows installation (or service pack installation) would put here. Editing will have no effect.
LMHOSTS.SAM C:\WINDOWS\I386 - Same dealy except this isn't the file you wanted.
Hosts C:\Program Files\Spybot -Search & Destroy\Includes - This is probably spybot's backup of your hosts file (spyware apps protect it from spyware).
hostsfile.hst C:\Program Files\Webroot\Spy Sweeper\Masters - Same thing, this is spy sweeper's backup of your hosts file.
hosts C:\WINDOWS\system32\drivers\etc - This is the host file you want to edit.
HOSTS.bak C:\WINDOWS\system32\drivers\etc - This is a backup of the hosts file you want to edit.
Imhosts C:\WINDOWS\system32\drivers\etc - This file is not what you wanted to edit. It keeps windows' info about where other computers are on the network.

Thanks for the help guys!